JPWO2013146995A1 - Pressure sensor and pressure sensor module - Google Patents

Abstract

Insulating substrate 2, organic transistor 10 provided on one main surface of insulating substrate 2, voltage power supply 30 for applying a predetermined voltage to source electrode 12 of organic transistor 10, and insulating substrate 2 A pressure-sensitive conductor 20 arranged in parallel and connected in series with the source electrode 12, on an xy coordinate plane parallel to the main surface of the pressure-sensitive conductor 20 to which pressure is applied according to a pressing operation; The organic transistor 10 and the pressure-sensitive conductor 20 are arranged in parallel at different positions and provide a pressure sensor that can be electrically connected according to a pressing operation.

Description

  The present invention relates to a flexible pressure sensor and a pressure sensor module.

  Regarding the designated countries that are allowed to be incorporated by reference, the Japanese Patent Application No. 2012-80197 filed in Japan on March 30, 2012, and the Japanese Patent Application No. 2012 filed in Japan on September 24, 2012 No. 209265 and the contents described in Japanese Patent Application No. 2012-209266 filed in Japan on September 24, 2012 are incorporated herein by reference and made a part of the description of this specification.

  With regard to this type of technology, there is known a flexible flexible detection device in which a pressure sensor in which an organic transistor and a pressure-sensitive conductive rubber sheet are combined is arranged in a planar shape (Patent Document 1).

JP-A-2005-150146

  However, this flexible detection device has a problem that since the pressure-sensitive rubber sheet is laminated on the organic transistor in the height direction, the height of the detection device is increased and it is difficult to reduce the thickness.

  The problem to be solved by the present invention is to provide a thin pressure sensor and a pressure sensor module.

  [1] The present invention relates to an insulating base material, an organic transistor provided on one main surface side of the insulating base material, a voltage power source for applying a predetermined voltage to a source electrode of the organic transistor, and the insulating property An xy coordinate parallel to a main surface of the pressure-sensitive conductor to which pressure is applied according to a pressing operation, the pressure-sensitive conductor disposed substantially parallel to the base material and connected in series with the source electrode On the surface, the organic transistor and the pressure-sensitive conductor are arranged in parallel at different positions, and can be electrically connected in accordance with a pressing operation. Solve.

  [2] In the above invention, in the thickness direction of the pressure sensor parallel to the thickness direction of the insulating base material, the height position of the installation surface of the pressure sensitive conductor and the height of the installation surface of the organic transistor It can comprise so that the difference with a position may become less than predetermined value.

  [3] In the above invention, at least a part of the installation surface of the pressure-sensitive conductor and at least a part of the installation surface of the organic transistor can be formed on the same xy coordinate plane.

  [4] In the above invention, the electrode to which the pressure-sensitive conductor is connected can be configured as a source electrode of the organic transistor.

  [5] In the above invention, the pressure-sensitive conductor included in the pressure sensor includes a first pressure-sensitive conductive layer and a second pressure-sensitive conductive layer having different pressure resistance characteristics, and the first pressure-sensitive conductive layer includes: The rate of change in resistance with respect to pressure in the first pressure region is higher than the rate of change in resistance with respect to pressure in the second pressure region other than the first pressure region, and the second pressure-sensitive conductive layer corresponds to the pressure in the second pressure region. The resistance change rate can be configured to be higher than the resistance change rate with respect to the pressure in the second pressure region of the first pressure-sensitive conductive layer.

[6] The second invention from a different viewpoint is to provide a pressure sensor module that maintains or improves the detection accuracy of the surface pressure distribution in a wide pressure region regardless of the strength of the input pressing force. .
According to a second aspect of the present invention, there is provided an insulating base material, an organic transistor provided on one main surface of the insulating base material, a voltage power source for applying a predetermined voltage to a source electrode of the organic transistor, and the source electrode in series. A pressure sensor or a pressure sensor group comprising a plurality of the pressure sensors, and a word line connected to each of the pressure sensors arranged two-dimensionally in a predetermined area And a bit line, and the pressure sensor or the pressure sensor group adjacent to each other along either the word line or the bit line has a pressure detection characteristic different from each other. This solves the above problem.

  [7] In the above invention, the pressure sensitive conductors of the pressure sensors adjacent to each other along either the word line or the bit line, or adjacent to either the word line or the bit line. The pressure-sensitive conductor groups of the matching pressure sensor groups can be configured to have different pressure resistance characteristics.

  [8] In the above invention, one of the pressure-sensitive conductors of the pressure-sensitive conductors of the pressure sensors adjacent to each other or the pressure-sensitive conductor group of the pressure sensor groups adjacent to each other. In the pressure-sensitive conductor group, the resistance change rate with respect to the pressure in the first pressure region is higher than the resistance change rate with respect to the pressure in the second pressure region other than the first pressure region, and the other pressure-sensitive conductor or the pressure-sensitive conductor group. The conductor group has a resistance change rate with respect to the pressure in the second pressure region higher than the resistance change rate with respect to the pressure in the one pressure-sensitive conductor or the second pressure region of the pressure-sensitive conductor group. Can be configured.

  [9] In the above invention, the pressure-sensitive conductors of the pressure sensors adjacent to each other along either the word line or the bit line can be formed using different pressure-sensitive conductive inks. .

  [10] In the above invention, the pressure-sensitive conductor groups of the pressure sensor groups adjacent to each other along either the word line or the bit line are a plurality of different pressure-sensitive conductive inks or different combinations. The pressure-sensitive conductive ink can be used.

  [11] In the above invention, the pressure-sensitive conductor included in the pressure sensor can be configured to have a plurality of pressure-sensitive conductive layers having different pressure resistance characteristics.

  [12] In the above invention, the pressure-sensitive conductor includes a first pressure-sensitive conductive layer and a second pressure-sensitive conductive layer, and the first pressure-sensitive conductive layer has a resistance change rate with respect to pressure in a third pressure region. The resistance change rate with respect to the pressure in the fourth pressure region other than the third pressure region is higher, and the second pressure sensitive conductive layer has a resistance change rate with respect to the pressure in the fourth pressure region. The rate of resistance change with respect to the pressure in the fourth pressure region of the layer may be higher.

[13] A third invention according to a different aspect is to provide a pressure sensor having good sensitivity to a pressing operation regardless of the strength of an applied pressing force.
3rd invention is an insulating base material, the organic transistor provided in one main surface of the said insulating base material, the voltage power source which applies a predetermined voltage to the source electrode of the said organic transistor, the said voltage power source, and the said A pressure-sensitive conductor disposed between the source electrode and connected in series with the source electrode, wherein the pressure-sensitive conductor includes a first pressure-sensitive conductive layer and a second pressure-sensitive layer having different pressure resistance characteristics. Solving the above problem by providing a pressure sensor comprising a conductive layer, and further comprising a spacer that forms a space between the first pressure-sensitive conductive layer and the second pressure-sensitive conductive layer To do.

  [14] In the first pressure-sensitive conductive layer of the above invention, the rate of change in resistance with respect to pressure in the first pressure region is higher than the rate of change in resistance with respect to pressure in the second pressure region other than the first pressure region. The pressure-sensitive conductive layer may be configured such that a resistance change rate with respect to the pressure in the second pressure region is higher than a resistance change rate with respect to the pressure in the second pressure region of the first pressure-sensitive conductive layer. it can.

  [15] In the above invention, the first pressure-sensitive conductive layer and the second pressure-sensitive conductive layer include a main surface of the first pressure-sensitive conductive layer to which pressure is applied and a main surface of the second pressure-sensitive conductive layer. It can arrange | position so that a surface may become parallel and can be electrically connected in series according to pressing operation.

  [16] In the above invention, the first pressure-sensitive conductive layer and the second pressure-sensitive conductive layer include one main surface of the first pressure-sensitive conductive layer to which pressure is applied and the second pressure-sensitive conductive layer. It can arrange | position so that one main surface may mutually face, and it can comprise so that it can connect electrically in series according to pressing operation.

  [17] In the above invention, the first pressure-sensitive conductive layer and the second pressure-sensitive conductive layer include a main surface of the first pressure-sensitive conductive layer to which pressure is applied and a main surface of the second pressure-sensitive conductive layer. It can be arranged in parallel at different positions on the xy coordinates along the surface, and can be electrically connected in series according to the pressing operation.

  [18] In the above invention, further comprising: a first pad electrode that can contact or contact the first pressure-sensitive conductive layer; and a second pad electrode that can contact or contact the second pressure-sensitive conductive layer, The first pad electrode is electrically connected to either the source electrode or the voltage power source, and the second pad electrode is electrically connected to either the source electrode or the voltage power source. can do.

  [19] In the above invention, the space is provided between the first pressure-sensitive conductive layer and the first pad electrode or between the second pressure-sensitive conductive layer and the second pad electrode. A spacer can be further provided.

  [20] In the above invention, the first pressure-sensitive conductive layer and the second pressure-sensitive conductive layer may have a printing pattern formed by printing using a pressure-sensitive conductive ink containing a conductive material. it can.

  According to the first invention, the organic transistor and the pressure sensitive conductor are arranged in parallel at different positions on the xy coordinates parallel to the main surface of the pressure sensitive conductor to which pressure is applied during the pressing operation. A thin pressure sensor can be provided.

  According to the second aspect of the present invention, since the pressure sensors or pressure sensor groups having different pressure detection characteristics are arranged adjacent to each other, the resistance value change of the pressure-sensitive conductor can be increased in a wide pressure region. For this reason, even if the pressing force applied at the time of the input operation varies widely in the low pressure to high pressure region, the surface pressure distribution can be measured. As a result, it is possible to provide a pressure sensor module that maintains or improves the measurement accuracy of the surface pressure distribution in a wide pressure region regardless of the magnitude of the pressing force applied during the input operation.

  According to the third aspect of the present invention, the pressure-sensitive conductor connected in series with the source electrode is connected between the source electrode of the organic transistor and the voltage power source. Since it is composed of conductive layers and these are arranged through a space so that they can be electrically connected in accordance with the pressing operation, the amount of variation in the potential difference between the source and drain in a wide pressure region can be increased. The movable region of the first pressure-sensitive conductive layer and the second pressure-sensitive conductive layer during the pressing operation can be ensured. As a result, it is possible to provide a pressure sensor that has good sensitivity to the pressing force regardless of the strength of the pressing force, and has improved on-off recognition sensitivity in which the conduction state and the insulating state are switched according to the pressing operation.

It is a circuit diagram of a unit composition of a pressure sensor concerning a 1st embodiment of the present invention. It is sectional drawing of the unit structure of the pressure sensor which concerns on 1st Embodiment of this invention. FIG. 3 is a III-III cross section of the pressure sensor shown in FIG. 2. It is a graph which shows an example of the pressure resistance characteristic of the pressure-sensitive conductive layer of the pressure sensor which concerns on 1st Embodiment of this invention, and a pressure-sensitive conductor. 1 is a circuit diagram of a pressure sensor module according to a first embodiment of the present invention. It is a 1st schematic diagram for demonstrating the pressure resistance characteristic of the pressure sensor arrange | positioned two-dimensionally. It is a 2nd schematic diagram for demonstrating the pressure resistance characteristic of the pressure sensor group arrange | positioned two-dimensionally. It is a 3rd schematic diagram for demonstrating the pressure resistance characteristic of the pressure sensor group arrange | positioned two-dimensionally. It is a 4th schematic diagram for demonstrating the pressure resistance characteristic of the pressure sensor group arrange | positioned two-dimensionally. It is a figure for demonstrating the effect | action at the time of pressing operation of the pressure sensor module which concerns on 1st Embodiment of this invention. It is process sectional drawing for demonstrating an example of the manufacturing method of the pressure sensor which concerns on 1st Embodiment of this invention. It is process sectional drawing for demonstrating an example of the manufacturing method of the pressure sensor which concerns on 1st Embodiment of this invention. It is process sectional drawing for demonstrating an example of the manufacturing method of the pressure sensor which concerns on 1st Embodiment of this invention. It is process sectional drawing for demonstrating an example of the manufacturing method of the pressure sensor which concerns on 1st Embodiment of this invention. It is process sectional drawing for demonstrating an example of the manufacturing method of the pressure sensor which concerns on 1st Embodiment of this invention. It is process sectional drawing for demonstrating an example of the manufacturing method of the pressure sensor which concerns on 1st Embodiment of this invention. It is process sectional drawing for demonstrating an example of the manufacturing method of the pressure sensor which concerns on 1st Embodiment of this invention. It is process sectional drawing for demonstrating an example of the manufacturing method of the pressure sensor which concerns on 1st Embodiment of this invention. It is sectional drawing of the unit structure of the pressure sensor which concerns on 2nd Embodiment of this invention. It is a figure for demonstrating the effect | action at the time of pressing operation of the pressure sensor module which concerns on 2nd Embodiment of this invention. It is process sectional drawing for demonstrating an example of the manufacturing method of the pressure sensor which concerns on 2nd Embodiment of this invention. It is process sectional drawing for demonstrating an example of the manufacturing method of the pressure sensor which concerns on 2nd Embodiment of this invention. It is process sectional drawing for demonstrating an example of the manufacturing method of the pressure sensor which concerns on 2nd Embodiment of this invention. It is process sectional drawing for demonstrating an example of the manufacturing method of the pressure sensor which concerns on 2nd Embodiment of this invention. It is process sectional drawing for demonstrating an example of the manufacturing method of the pressure sensor which concerns on 2nd Embodiment of this invention. It is process sectional drawing for demonstrating an example of the manufacturing method of the pressure sensor which concerns on 2nd Embodiment of this invention. It is process sectional drawing for demonstrating an example of the manufacturing method of the pressure sensor which concerns on 2nd Embodiment of this invention. It is process sectional drawing for demonstrating an example of the manufacturing method of the pressure sensor which concerns on 2nd Embodiment of this invention. It is process sectional drawing for demonstrating an example of the manufacturing method of the pressure sensor which concerns on 2nd Embodiment of this invention. It is sectional drawing of the unit structure of the pressure sensor which concerns on the 1st example of 2nd Embodiment of this invention. It is sectional drawing of the unit structure of the pressure sensor which concerns on the 2nd example of 2nd Embodiment of this invention. It is III-III sectional drawing of the unit structure of the pressure sensor which concerns on the 3rd example of 2nd Embodiment of this invention shown in FIG.

<First Embodiment>
Hereinafter, a pressure sensor according to a first embodiment of the present invention will be described with reference to the drawings. In the present embodiment, an example in which the pressure sensor module according to the present invention is a pressure sensor module in which the pressure sensors are arranged in a matrix and is applied to a touch panel type input device will be described.

  The pressure sensor 1 of the present embodiment is arranged in a matrix along a predetermined operation surface that receives a pressing operation (touch operation), and constitutes a touch panel display. The application of the pressure sensor 1 of the present embodiment is not limited to a touch panel display, and can be applied to various sensors such as a fingerprint sensor and interfaces of various devices such as switches.

  FIG. 1 is a circuit diagram of a pressure sensor 1 combining an organic transistor (FET) 10 and a pressure-sensitive conductor 20 as a unit configuration of a pressure sensor module.

  As shown in FIG. 1, the pressure sensor 1 of this embodiment includes an organic transistor 10, a pressure-sensitive conductor 20, and a voltage power supply 30. In the pressure sensor 1 of the present embodiment, the pressure-sensitive conductor 20 is provided between the voltage power supply 30 and the organic transistor 10, and the source electrode 12 of the organic transistor 10 and the pressure-sensitive conductor 20 are connected in series. It has a structure.

As shown in the figure, the organic transistor 10 of the present embodiment is a transistor using the organic semiconductor layer 15, and includes a gate electrode 11, a source electrode 12, and a drain electrode 13 together with the organic semiconductor layer 15. . The voltage power supply 30 of this embodiment applies a predetermined voltage V _DD to the source electrode 12 of the organic transistor 10. The organic transistor 10 outputs a signal corresponding to the current value between the source and the drain when the predetermined voltage V _DD is applied to the external signal processing device 40. Based on the signal acquired from the organic transistor 10, the signal processing device 40 detects the pressing position or the pressing force related to the pressing operation.

  In the present embodiment, the pressure-sensitive conductor 20 is provided between the voltage power supply 30 and the organic transistor 10. The source electrode 12 of the organic transistor 10 and the pressure sensitive conductor 20 have a structure connected in series.

When the organic transistor 10 is the voltage of the word line (WL) to turn on state (V _WL) to set the power voltage V _DD, in the linear region of the output characteristics of the organic transistor 10, the source - the amount of current flowing between the drain It changes in proportion to the potential difference between the source and drain. Further, the potential difference between the source and drain when a constant voltage is applied by the voltage power supply 30 depends on the resistance value of the pressure-sensitive conductor 20 connected in series with the source electrode 12.

  Since the resistance value of the pressure-sensitive conductor 20 in the present embodiment changes according to the pressure received by pressing, the pressure-sensitive conductor 20 functions as a variable resistance member in the organic transistor 10 of the present embodiment. That is, when the resistance value of the pressure-sensitive conductor 20 decreases due to the pressure application, the potential difference between the source and the drain increases, and the amount of current flowing increases. By detecting this change in the amount of current, the amount of pressure applied to the pressure sensor 1 during the pressing operation can be detected. The pressure sensitive conductor 20 will be described in detail later.

  Then, based on FIG.2 and FIG.3, the structure of the pressure sensor 1 of this embodiment is demonstrated. 2 is a cross-sectional view showing a unit configuration of the pressure sensor 1, and is also a II-II cross-sectional view of FIG. 3 is a cross-sectional view of the pressure sensor 1 shown in FIG. 2 taken along the line III-III. As shown in FIG. 2, the gate electrode 11, the source electrode 12, and the drain electrode 13 constituting the organic transistor 10 are formed on one main surface side of the insulating base 2 and covered with the gate insulating layer 14. An organic semiconductor layer 15 is formed above 11 (upward in the drawing along the stacking direction, hereinafter the same). An insulating layer 17 is formed on the organic semiconductor layer 15. The insulating layer 17 that protects the organic semiconductor layer 15 may be a single layer or a plurality of layers.

  The main surface of the pressure-sensitive conductor 20 is mainly applied with a pressure along the direction of the arrow F in accordance with the pressing operation. The main surface of the pressure-sensitive conductor 20 is parallel to the xy coordinate plane in the coordinate system shown in the drawing. Incidentally, in this embodiment, the main surface of the cover member 50 provided with the operation surface P and the main surface of the insulating substrate 2 on which the organic transistor 10 is formed are also parallel to the xy coordinate plane.

  As shown in FIG. 2, in the pressure sensor 1 of the present embodiment, the organic semiconductor layer 15, the gate electrode 11, the source electrode 12, and the drain electrode 13 (organic transistor 10) are disposed on the main surface side of the insulating substrate 2. And the first pressure-sensitive conductive layer 21 of the pressure-sensitive conductor 20 are formed in different regions. That is, as shown in FIGS. 2 and 3, the pressure-sensitive conductor 20 (the first pressure-sensitive conductive layer 21 and the second pressure-sensitive conductive layer 22) on the xy coordinate plane parallel to the main surface of the pressure-sensitive conductor 20. And the organic transistor 10 (the organic semiconductor layer 15, the gate electrode 11, the source electrode 12, and the drain electrode 13) are arranged in parallel at different positions without overlapping.

  As described above, the organic transistor 10 and the pressure-sensitive conductor 20 are arranged in parallel so as not to overlap with each other, so that the pressure sensor 1 can be thinned. Further, when the pressure-sensitive conductor 20 and the organic transistor 10 are configured to overlap each other, there is a disadvantage that the pressing force is also applied to the organic transistor 10 when the pressing force is applied to the pressure-sensitive conductor 20. However, such inconvenience can be eliminated by arranging them in parallel as in the present embodiment.

  Although not particularly limited, in the pressure sensor 1 of the present embodiment, the height position of the installation surface of the pressure-sensitive conductor 20 and the organic transistor in the thickness direction of the pressure sensor 1 parallel to the thickness direction of the insulating substrate 2. 10 is configured such that the difference from the height position of the installation surface is less than a predetermined value. Specifically, the height of the installation surface with respect to the insulating substrate 2 in any one of the members of the organic semiconductor layer 15, the gate electrode 11, the source electrode 12, and the drain electrode 13 constituting the organic transistor 10; The height difference between the pressure-sensitive conductor 20 and the height of the installation surface with respect to the insulating base material 2 is configured to be less than a predetermined value. Of course, another member is interposed between the insulating base material 2, that is, another member is laminated on the insulating base material 2, and the organic transistor 10 (including constituent members) is formed on the other member. And the aspect in which the pressure-sensitive conductor 20 was installed is also included.

  In the example shown in the figure, the organic transistor 10 of the present embodiment is such that the lowest part (a part on the lower side in the figure) of the organic semiconductor layer 15 which is a member constituting the organic transistor 10 is above the gate insulating layer 14. It is installed on the upper side of the insulating substrate 2 in contact with the (main surface). The height of the organic transistor when the main surface of the insulating base material 2 is used as a reference is d1. Further, the pressure-sensitive conductor 20 of the present embodiment has a first pressure-sensitive conductive layer 21 on the electrode (source electrode 12, first pad electrode 18) (main surface) formed on the gate insulating layer 14. It is installed in contact. The height of the installation surface of the first pressure-sensitive conductive layer 21 when the main surface of the insulating substrate 2 is used as a reference is d2. The height position d1 of the installation surface of the organic transistor 10 (including the organic semiconductor layer 15 and other members constituting the organic transistor 10, the same applies hereinafter) and the height position d2 of the installation surface of the first pressure-sensitive conductive layer 21 The difference is d. The pressure sensor 1 of the present embodiment is characterized in that the height difference d is less than a predetermined value. From the viewpoint of reducing the thickness of the pressure sensor 1, the height difference d can be set by multiplying the thickness of the pressure sensor 1 by a predetermined ratio. Alternatively, the pressure sensor 1 can be set by multiplying the thickness of the insulating base material 2 that is a thick member by a predetermined ratio. In this example, the difference between the height position of the installation surface of the first pressure-sensitive conductive layer 21 and the height position of the installation surface of the organic transistor 10 is 0.05 μm or more and 50 μm or less, and further 0.05 μm or more and 30 μm or less. Furthermore, it can be 0.05 μm or more and 10 μm or less. The height difference d between the height position d1 of the installation surface of the organic semiconductor layer 15 of this example and the height position d2 of the installation surface of the first pressure-sensitive conductive layer 21 is an electrode (source electrode 12, first pad electrode 18). The thickness is 0.05 μm or more and 10 μm or less.

  The difference in height position (height difference) is less than a predetermined value when the height difference is zero, that is, the organic transistor 10 (including the organic semiconductor layer 15 and other members constituting the organic transistor 10). This includes a case where at least a part of the installation surface and at least a part of the installation surface of the pressure-sensitive conductor 20 are formed on an xy coordinate plane parallel to the main surface of the insulating base 2. In the pressure-sensitive sensor 1 of this embodiment shown in FIG. 2, the bottom surface (installation surface) of the organic semiconductor layer 15 of the organic transistor 10 is the main surface of the gate insulating layer 14, the main surface above the drain electrode 13, and the source electrode. 12 is in contact with the upper main surface. The bottom surface (installation surface) of the first pressure-sensitive conductive layer 21 is in contact with the upper main surface of the source electrode 12. That is, when the upper main surface of the source electrode 12 formed on the main surface of the insulating substrate 2 (xy coordinate plane parallel to the main surface of the insulating substrate 2) is used as a reference, the bottom surface of the organic semiconductor layer 15 The height of a part of the (installation surface) and the height of a part of the bottom surface (installation surface) of the first pressure-sensitive conductive layer 21 are the same, and the height difference is zero.

  As described above, the organic transistor 10 and the pressure-sensitive conductor 20 are arranged in parallel so as not to overlap each other, and the height of the installation surface of the organic transistor 10 and the pressure-sensitive conductor 20 is made less than a predetermined value. Thus, the pressure sensor 1 can be further reduced in thickness.

  As shown in FIG. 2, the pressure-sensitive conductor 20 of the present embodiment includes a first pressure-sensitive conductive layer 21 and a second pressure-sensitive conductive layer 22, and the first pressure-sensitive conductive layer 21 and the second pressure-sensitive conductor 22. A space 23 is formed between the conductive layer 22 and the conductive layer 22. In the present embodiment, the spacer 60 is disposed between the insulating base material 2 and the cover member 50 with the adhesive layers 61a and 61b interposed therebetween. The spacer 60 is connected to the first pressure-sensitive conductive layer 21 and the second pressure-sensitive conductive material. A space 23 is formed between the layer 22 and between the insulating layer 17 covering the organic semiconductor layer 15 and the cover member 50. A second pressure-sensitive conductive layer 22 is formed on the other main surface (lower main surface in the drawing) of the cover member 50. In the example shown in FIG. 2, one main surface 21 </ b> A of the first pressure-sensitive conductive layer 21 and one main surface 22 </ b> A of the second pressure-sensitive conductive layer 22 are surfaces to which a pressing force is applied along the arrow F direction in the drawing. Yes, both main surfaces 21A and 22A are arranged substantially parallel to or parallel to each other. Further, both the main surfaces 21A and 22A are disposed substantially perpendicular to or perpendicular to the direction in which the pressing force is applied (direction F in the figure). Furthermore, the one main surface 21A of the first pressure-sensitive conductive layer 21 and the one main surface 22A of the second pressure-sensitive conductive layer 22 are arranged so as to face each other through the space 23.

  The spacer 60 of the present embodiment shown in FIGS. 2 and 3 includes a first opening 62 </ b> A that forms a first space 231 for housing the organic transistor 10 in the arrangement region of the organic transistor 10, and the pressure-sensitive conductor 20. The second opening 62B that forms the second space 232 for accommodating the pressure-sensitive conductor 20 is provided in the arrangement region. It is preferable that portions other than the first opening 62A and the second opening 62B have a structure (honeycomb structure or the like) that can maintain solidity or strength. In the present embodiment, the opening area of the first opening 62A is smaller than the opening area of the second opening 62B. The pressing operation is performed by reducing the first opening 62A that forms the first space 231 that accommodates the organic transistor 10 and increasing the second opening 62B that forms the second space 232 that accommodates the pressure-sensitive conductor 20. In some cases, the pressing force applied to the organic transistor 10 can be suppressed without hindering the application of the pressing force to the pressure-sensitive conductor 20. Since the pressing force applied to the organic transistor 10 can be reduced, the output fluctuation of the organic transistor 10 can be suppressed and the detection accuracy of the pressure sensor 1 can be improved. Moreover, since the pressing force applied to the organic transistor 10 can be reduced, mechanical consumption of the organic transistor 10 can be prevented, and the product life of the pressure sensor 1 can be extended.

  The spacer 60 of the present embodiment can be made of an insulating base material such as polyethylene terephthalate. The opening (the plane or bottom surface of the space 23) formed by the spacer 60 can be appropriately set according to the size of the operation switch. The spacer 60 of this example is fixed to the gate insulating layer 14 and the cover member 50 by adhesive layers 61a and 61b. The thickness of the spacer 60 including the adhesive layers 61a and 61b (the height of the space 23) can be 50 μm to 200 μm, preferably about 75 μm to 150 μm, and more preferably 100 μm or less. The thickness of the spacer 60 in this example is 75 μm or less.

  In the space 232 formed by the spacer 60 and the adhesive layers 61a and 61b, the first pad electrode 18, the second pad electrode 19, the first pressure-sensitive conductive layer 21, and the second pressure-sensitive conductive layer 22 are accommodated. A space 23 is formed between the first pressure-sensitive conductive layer 21 and the second pressure-sensitive conductive layer 22 so that contact and separation are possible. The distance between the first pressure-sensitive conductive layer 21 and the second pressure-sensitive conductive layer 22 in this example is about 30 μm. The distance between the first pressure-sensitive conductive layer 21 and the second pressure-sensitive conductive layer 22 is not particularly limited, and the thickness of the gate insulating layer 14, the thickness of the cover member 50, the first pressure-sensitive conductive layer 21, and the second sense. Various factors such as the thickness of the pressure conductive layer 22, the thickness of the spacer 60, the pressure resistance characteristics of the pressure sensitive conductive layers 21 and 22, the magnitude of the pressure applied during the pressing operation, and the threshold value for on / off identification It can be set as appropriate based on experiments.

  When the user performs a pressing operation and the cover member 50 is pressed along the direction of arrow F in FIG. 2, the one principal surface 21 </ b> A of the first pressure-sensitive conductive layer 21 and the one principal surface 22 </ b> A of the second pressure-sensitive conductive layer 22. Since a pressing force in the direction of arrow F is applied to the second pressure-sensitive conductive layer 22, the second pressure-sensitive conductive layer 22 arranged on the cover member 50 side moves in the space 23 to the gate insulating layer 14 side. When the second pressure-sensitive conductive layer 22 contacts the first pressure-sensitive conductive layer 21, the first pressure-sensitive conductive layer 21 and the second pressure-sensitive conductive layer 22 are electrically connected in series and are in a conductive state (ON State). On the other hand, when the applied pressing force is released, the second pressure-sensitive conductive layer 22 is separated from the first pressure-sensitive conductive layer 21 and moves in the space 23 toward the cover member 50. Thus, the space 23 formed between the first pressure-sensitive conductive layer 21 and the second pressure-sensitive conductive layer 22 becomes a movable region of the first pressure-sensitive conductive layer 21 and the second pressure-sensitive conductive layer 22. Therefore, the first pressure-sensitive conductive layer 21 can be brought into contact with or separated from the second pressure-sensitive conductive layer 22 in accordance with the pressing operation. In order to bring the first pressure-sensitive conductive layer 21 into contact with the second pressure-sensitive conductive layer 22, it is necessary to apply a pressing force for moving the second pressure-sensitive conductive layer 22 by a distance corresponding to the thickness of the space 23. is there. The first pressure-sensitive conductive layer 21 and the second pressure-sensitive conductive layer can be brought into contact with the second pressure-sensitive conductive layer 22 when a pressing force of a predetermined value or more is applied. The ON state due to the contact of 22 and the OFF state due to the separation between the first pressure-sensitive conductive layer 21 and the second pressure-sensitive conductive layer 22 can be clearly distinguished.

  Incidentally, the first pressure-sensitive conductive layer 21 and the second pressure-sensitive conductive layer 22 can be laminated so as to be in direct contact without forming the space 23. Since the current flows through the pressure-sensitive conductive layer when pressed, the pressure-sensitive conductive layer is almost in an insulating state when it is simply in contact with the pressure-sensitive conductive layer, and even if a current flows, it is very small. On the other hand, when a pressing operation (application of a pressing force) is started, the value of the current that flows according to the pressing force increases. The pressure-sensitive conductor 20 having such a configuration is excellent in that the current value can be controlled according to the application of the pressing force, but whether or not the pressing force is applied, that is, the on / off timing. It may be difficult to detect. In the pressure-sensitive conductor 20 of the present embodiment, a space 23 is formed between the first pressure-sensitive conductive layer 21 and the second pressure-sensitive conductive layer 22, and the second pressure-sensitive conductive layer 22 opens the space 23 by a pressing operation. The on-state is identified when it moves and contacts the first pressure-sensitive conductive layer 21. Since a pressing force of a predetermined amount or more is required to identify the ON state, it can be determined that the conducting state (ON state) is applied when a pressing force of a certain predetermined amount or more is applied. In the present embodiment, by forming a space 23 in which the first pressure-sensitive conductive layer 21 and the second pressure-sensitive conductive layer 22 can move, the on-off recognition sensitivity according to the pressing operation is improved.

  The pressure sensor 1 of the present embodiment includes a first pad electrode 18 that can contact or contact the first pressure-sensitive conductive layer 21, and a second pad electrode 19 that can contact or contact the second pressure-sensitive conductive layer 22. In addition, the first pad electrode 18 is electrically connected to either the source electrode 12 or the voltage power supply 30, and the second pad electrode 19 is also electrically connected to either the source electrode 12 or the voltage power supply 30. Can be configured.

  In the example shown in FIG. 2, the first pad electrode 18 is formed so as to contact the lower side surface of the first pressure-sensitive conductive layer 21 disposed on the lower side of the pressure-sensitive conductor 20 of the present embodiment. . The first pad electrode 18 also functions as the source electrode 12 of the organic transistor 10. That is, one electrode functions as the source electrode 12 of the organic transistor 10 and also functions as the first pad electrode 18 of the pressure-sensitive conductor 20. By configuring in this way and reducing the number of components, the pressure sensor 1 can be further reduced in thickness. Moreover, since the 1st pad electrode 18 and the source electrode 12 can be formed simultaneously, manufacturing cost can also be reduced.

  The first pressure-sensitive conductive layer 21 (pressure-sensitive conductor 20) is electrically connected to the first pad electrode 18 and the source electrode 12 in series. Further, as shown in the figure, the upper surface side of the second pressure-sensitive conductive layer 22 disposed on the upper side of the pressure-sensitive conductor 20, that is, between the cover member 50 and the second pressure-sensitive conductive layer 22. A second pad electrode 19 is formed. The second pressure-sensitive conductive layer 22 is electrically connected to the voltage power supply 30 through the second pad electrode 19. The second pad electrode 19 and the first pad electrode 18 connected to the voltage power source 30 can be conducted through the pressure-sensitive conductor 20 (pressure-sensitive conductive layers 21 and 22). FIG. 2 shows an example in which the first pressure-sensitive conductive layer 21 is disposed below the second pressure-sensitive conductive layer 22, but the second pressure-sensitive conductive layer 22 is on the lower side, that is, on the gate insulating layer 14 side. It can also be arranged.

  Here, the pressure-sensitive conductor 20 including the first pressure-sensitive conductive layer 21 and the second pressure-sensitive conductive layer 22 will be described. The pressure-sensitive conductor 20 of this embodiment is a pressure-sensitive conductive layer formed by printing using a pressure-sensitive conductive ink in which conductive particles and elastic particles are dispersed in a binder, and conductive particles and elastic particles are dispersed in the binder. A pressure-sensitive conductive layer formed by thinly forming a pressure-sensitive conductive material, and a pressure-sensitive conductive layer obtained by slicing a pressure-sensitive conductive sheet in which conductive particles and elastic particles are dispersed in a binder.

  Although not particularly limited, as the conductive particles, metal particles, semiconductor particles such as indium-doped tin oxide, or carbon particles can be used. As the elastic particles, organic elastic fillers and inorganic oxide fillers can be used. As the organic elastic filler, particles made of polymers such as silicone, acrylic, styrene, and urethane, nylon 6, nylon 11, nylon 12, and the like can be used. The particles are preferably spherical. As the binder, silicone rubber materials, polyurethane resin materials, epoxy resin materials, phenol resin materials, polyester resin materials, and the like can be used. In particular, a binder containing a polyester-based resin, especially a copolyester resin, can improve the adhesion to the substrate on which the pressure-sensitive conductive layers 21 and 22 are formed. As the binder, a crosslinking type, for example, an isocyanate compound or an amine compound can be used.

  Although not particularly limited, as the pressure-sensitive conductive ink, for example, one in which graphite is dispersed in a silicone material or one in which silver particles are dispersed in a polyester resin can be used. However, the pressure-sensitive conductive ink known at the time of filing or commercially available can be appropriately used.

  Further, the pressure-sensitive conductor 20 of this embodiment has a pressure-sensitive conductive layer in which a pressure-sensitive conductive sheet made of a material in which conductive particles are dispersed in elastic polymer rubber or the like is thinly formed. May be. Although not particularly limited, as the pressure-sensitive conductive layer of the present embodiment, for example, a pressure-sensitive conductive material formed by adding graphite to silicone rubber and formed into a thin layer can be used. When elastic particles such as silicone rubber are compressed when pressure is applied to the pressure sensitive conductor 20, conductive materials such as metal particles and graphite are brought into contact with each other, a conductive path is formed, and the resistance value decreases. The principle is to do. That is, when the pressure-sensitive conductor 20 is pressed and pressure is applied, the resistance value of the pressure-sensitive conductor 20 decreases due to this pressure application, and therefore the potential difference between the source and the drain increases and the amount of current flowing increases. If the pressing force applied to the pressure-sensitive conductor 20 and the amount of current are acquired in advance, the amount of pressure (pressing force) applied to the pressure sensor 1 is detected by reading the change in signal corresponding to the amount of current. Can do.

  Incidentally, the general thickness of the pressure-sensitive conductive rubber sheet is 100 μm, and if it is used as it is without slicing, the pressure-sensitive conductor 20 is also thickened and the thickness of the pressure sensor 1 is also thickened. On the other hand, as in this embodiment, the pressure-sensitive conductive layers 21 and 22 are formed by screen printing using a pressure-sensitive conductive ink, formed by thinly extending a pressure-sensitive conductive material, or pressure-sensitive conductive By forming the rubber sheet by thinly slicing it, the thickness can be reduced to about 30 μm or less. Therefore, the thickness of the pressure-sensitive conductor 20 can be reduced, and the height of the pressure sensor 1 can be reduced. it can.

  In the present embodiment, the first pressure-sensitive conductive layer 21 and the second pressure-sensitive conductive layer 22 constituting the pressure-sensitive conductor 20 have different pressure resistance characteristics. The pressure resistance characteristic of the present embodiment is a mode of change in resistance value with respect to an applied pressure value at the time of pressing. The pressure resistance characteristic can be evaluated based on a resistance value in a region of a predetermined applied pressure value, a change amount of the resistance value, and the like.

  Here, the reason why the pressure-sensitive conductive layers 21 and 22 having different pressure resistance characteristics are electrically connected in series will be described. FIG. 4 shows the pressure resistance characteristics of the first pressure-sensitive conductive layer 21 and the second pressure-sensitive conductive layer 22 formed by printing a material (ink) formed by dispersing graphite in a silicone material. The first pressure-sensitive conductive layer 21 shown in FIG. 4 exhibits a relatively high (large) resistance change rate in a low pressure region where the applied pressure during pressing is less than 20 kPa, but the resistance change rate in a medium to high pressure region of 20 kPa or more. Decreases rapidly (decreases). If only such a pressure-sensitive conductive layer is used as the pressure-sensitive conductor 20, the pressure change when the applied pressure at the time of pressing becomes 20 kPa or more cannot be detected accurately, and the sensitivity of the pressure sensor is lowered. On the other hand, if only a pressure-sensitive conductive layer having a high resistance change rate is used in a region where the applied pressure at the time of pressing is 20 kPa or more, the sensitivity of the pressure sensor is lowered in a region where the applied pressure is less than 20 kPa.

  In the present embodiment, the first pressure-sensitive conductive layer 21 and the second pressure-sensitive conductive layer 22 having a pressure resistance characteristic different from that of the first pressure-sensitive conductive layer 21 are opposed to each other via the space 23 formed by the spacer 60. The pressure sensitive conductor 20 is arranged. The second pressure-sensitive conductive layer 22 has a resistance change rate higher than the resistance change rate of the first pressure-sensitive conductive layer 21 as shown in FIG. 4 in a region where the applied pressure during pressing is 20 kPa or more. As described above, during the pressing operation, the second pressure-sensitive conductive layer 22 disposed on the cover member 50 side that receives the pressing force moves to the first pressure-sensitive conductive layer 21 side in response to the pressing operation. The second pressure-sensitive conductive layer 22 contacts the first pressure-sensitive conductive layer 21 and is electrically connected in series.

  When the first pressure-sensitive conductive layer 21 and the second pressure-sensitive conductive layer 22 having different pressure resistance characteristics are arranged so as to be electrically connected in series (including parallel arrangement, opposing arrangement, and parallel arrangement). At the time of connection, a high resistance change rate not only in the low pressure region where the applied pressure is less than 20 kPa but also in the medium and high pressure region where the applied pressure is 20 kPa or more as shown in “the combined resistance value in series connection” shown in FIG. Indicates. That is, the pressure resistance characteristic of the pressure-sensitive conductor 20 in which the first pressure-sensitive conductive layer 21 and the second pressure-sensitive conductive layer 22 shown in FIG. 4 are electrically connected in series is the first pressure-sensitive conductive layer 21 or the first pressure-sensitive conductive layer 21. 2 The resistance change rate is higher in a wide applied pressure region than the single pressure resistance characteristic of the pressure-sensitive conductive layer 22. FIG. 4 shows the pressure resistance characteristics of the pressure-sensitive conductor 20 when the first pressure-sensitive conductive layer 21 and the second pressure-sensitive conductive layer 22 are laminated. As shown in FIG. 2, the first pressure-sensitive conductive layer 21 and the second pressure-sensitive conductive layer 22 are arranged so as to face each other through a space 23, and are electrically connected in series when a pressing force is applied. The pressure resistance characteristics of the pressure-sensitive conductor 20 configured as described above also show the same pressure resistance characteristics except when pressing starts and when pressing is released.

  Although not particularly limited, in this embodiment, the resistance change rate with respect to the pressure in the first pressure region (corresponding to the low pressure region) of the applied pressure at the time of pressing is the second pressure region (corresponding to the medium and high pressure region) other than the first pressure region. The first pressure-sensitive conductive layer 21 having a resistance change rate with respect to the pressure in the second pressure region and the second pressure-sensitive conductive layer 21 having a resistance change rate with respect to the pressure in the second pressure region higher than the resistance change rate with respect to the pressure of the first pressure-sensitive conductive layer. The pressure-sensitive conductor 20 can be configured to include at least the conductive layer 22. The first pressure-sensitive conductive layer 21 and the second pressure-sensitive conductive layer 22 exhibiting the pressure resistance characteristics can be composed of a plurality of layers having different pressure resistance characteristics.

  The pressure resistance characteristic of the first pressure-sensitive conductive layer 21 is biased, and the resistance change rate with respect to the pressure in the first pressure region of the applied pressure at the time of pressing is greater than the resistance change rate with respect to the pressure in the second pressure region other than the first pressure region. If the resistance change rate in the second pressure region is low, the sensitivity in the second pressure region may be lowered if only the first pressure-sensitive conductive layer 21 is used. In order to compensate for such a sensitivity that decreases in the second pressure region, in the present embodiment, the second pressure-sensitive conductivity is such that the resistance change rate with respect to the pressure in the second pressure region is higher than the resistance change rate with respect to the pressure in the first pressure region. The pressure sensitive conductor 20 is used in which the pressure resistance characteristic is synthesized by arranging the layer 22 so that it can be electrically connected in series to the first pressure sensitive conductive layer 21 during the pressing operation.

  As described above, by using the plurality of pressure-sensitive conductive layers 21 and 22 that exhibit different resistance change rates depending on the applied pressure region (value range), the first pressure-sensitive conductive layer 21 having a low resistance change rate in a certain applied pressure region. The pressure resistance characteristics of the first pressure-sensitive conductive layer 21 can be obtained by arranging the second pressure-sensitive conductive layer 22 having a high resistance change rate in the applied pressure region so that it can be electrically connected in series. As a result, a synthesized pressure resistance characteristic having a high resistance change rate in a wide range can be obtained. As a result, good sensitivity as a pressure sensor can be maintained in both the first pressure region and the second pressure region.

  Here, a method for adjusting the pressure resistance characteristic of the pressure-sensitive conductor 20 (the pressure-sensitive conductive layers 21 and 22) (method for obtaining the pressure-sensitive conductor 20 having an arbitrary pressure resistance characteristic) will be described.

  First, when the pressure-sensitive conductive layers 21 and 22 are formed by screen printing using a pressure-sensitive conductive ink in which graphite and / or conductive particles are dispersed in a silicone material, or as the pressure-sensitive conductive layers 21 and 22, When using a thin layer of pressure-sensitive conductive sheet in which graphite and / or conductive particles are added to silicone rubber, each pressure-sensitive conductive material can be changed by changing the amount of conductive material such as graphite and / or conductive particles. It is possible to adjust the pressure resistance (PR) characteristics of the layer.

  When the pressure-sensitive conductive ink forming the pressure-sensitive conductive layers 21 and 22 contains silicone particles as elastic particles, the ratio of the silicone particles can be changed. Specifically, the amount of change in resistance value in the low pressure region can be increased by reducing the proportion of the silicone particles, and the amount of change in resistance value in the medium to high pressure region can be increased by increasing the proportion of the silicone particles.

  In the case where a thin layer of a pressure-sensitive conductive sheet obtained by adding graphite to silicone rubber is used as the pressure-sensitive conductive layers 21 and 22, these pressure resistance characteristics can be adjusted by adjusting the hardness of the pressure-sensitive conductive layers 21 and 22. Can be changed. This is because, if the hardness is different, the resistance value also changes because the degree of compression of the pressure-sensitive conductive layers 21 and 22 when pressed is different. For example, as the pressure-sensitive conductive layers 21 and 22 of the present embodiment, a sheet made of a rubber-based material such as silicone rubber can be used. In this case, a hardness adjusting agent such as a silica-based powder filler is used. The hardness of the silicone rubber can be adjusted. Although not particularly limited, in this embodiment, the first pressure-sensitive conductive layer 21 made of a material in which a hardness adjusting agent is added at a first addition rate with respect to the total amount of the rubber-based material, and the hardness adjusting agent is a rubber-based material. The pressure-sensitive conductor 20 can be configured by laminating the second pressure-sensitive conductive layer 22 made of a material added at a second addition rate different from the first addition rate relative to the total amount of the above. The magnitude relationship between the first addition rate and the second addition rate is not particularly limited, and can be set as appropriate according to the hardness adjusting agent.

  For example, when a silica-based powder filler is used as the hardness adjusting agent, if the amount of the silica-based powder filler added to the rubber-based material of the pressure-sensitive conductive layers 21 and 22 is large, the rubber hardness is high (hard). Conversely, when the addition amount is small, the rubber hardness tends to be low (soft). For this reason, in this embodiment, the hard first pressure-sensitive conductive layer 21 made of a rubber-based material to which a silica-based powder filler is added at a first addition rate with respect to the total amount of the rubber-based material, A soft second pressure-sensitive conductive layer 22 made of a rubber-based material to which a silica-based powder filler is added at a second addition rate lower than the first addition rate is opposed to the total amount of the material. Thus, a desired pressure-sensitive conductor 20 in which pressure resistance characteristics are synthesized can be configured.

  In the case where the rubber hardness of the pressure-sensitive conductive layers 21 and 22 is lowered (softened), a technique of adding silicone oil or increasing the amount of silicone oil as a hardness adjusting agent may be used. it can. That is, when obtaining the hard pressure-sensitive conductive layers 21 and 22, silicone rubber with a large amount of powder can be used, and when obtaining the soft pressure-sensitive conductive layers 21 and 22, silicone rubber with a large amount of oil can be used.

  In this embodiment, the pressure resistance characteristic can be adjusted by the addition amount of graphite, the addition amount of a hardness adjusting agent such as a silica-based powder filler, and the addition amount of silicone-based oil. , 22 is associated in advance with the addition amount, pressure-sensitive conductive layers 21 and 22 having arbitrary pressure resistance characteristics are prepared by adjusting the addition amount, and this is used. A pressure-sensitive conductor 20 having desired pressure resistance characteristics can be configured. As a result, the pressure sensor 1 having desired pressure resistance characteristics can be obtained.

  In this manner, the pressure-sensitive conductive layer 21 having a high resistance change rate in a region having a relatively low pressure value can be electrically connected to the pressure-sensitive conductive layer 22 having a high resistance change rate in a region having a medium to high pressure value. The pressure-sensitive conductor 20 is configured in such a manner that it is electrically inserted in series between the voltage power source 30 and the source electrode 12 of the organic transistor 10 to cause a large resistance change in a wide pressure region. Therefore, the potential difference between the source and the drain also increases, and as a result, the pressure sensor 1 having high sensitivity in a wide pressure region can be provided.

  Next, the pressure sensor module 100 will be described. FIG. 5 is a circuit diagram of a pressure sensor module in which a plurality of pressure sensors 1 having the above-described configuration are prepared and arranged two-dimensionally at predetermined pitches in the vertical and horizontal directions (along the xy axes). As shown in FIG. 5, the pressure sensors 1 are arranged in a predetermined region P. A word line WL and a bit line BL are wired along the arrangement direction (xy axis direction) of the pressure sensors 1 in the predetermined region P. In this example, the word lines WL are wired along the x-axis direction, and the bit lines BL are wired along the y-axis direction. The organic transistor 10 sends the detected signal and its own address signal to the signal processing device 40 via the word line WL and the bit line BL.

  In the present embodiment, the pressure sensors 1 having the same pressure detection characteristics may be arranged two-dimensionally, or the pressure sensors 1 having different pressure detection characteristics may be arranged two-dimensionally. The pressure detection characteristic here includes the detection characteristic for the pressure described above. In the present embodiment, the pressure detection characteristic of the pressure sensor 1 can be changed by changing the pressure resistance characteristic of the pressure-sensitive conductor 20 or by changing the pressure resistance characteristic of the pressure-sensitive conductive layers 21 and 22. .

  In the pressure sensor module 100 according to this embodiment, two pressure sensors 1 adjacent along either the word line WL or the bit line BL are two-dimensionally arranged so as to have different pressure detection characteristics. .

  6A to 6D are schematic views of pressure sensors arranged two-dimensionally within the predetermined region P1. Specifically, in this embodiment, as shown in FIG. 6A, the pressure sensor 1 (1A) having one pressure detection characteristic and the pressure sensor 1 (1B) having another pressure detection characteristic are staggered (staggered lattice). Arranged).

  Further, as shown in FIG. 6B, the pressure sensors 1 having the same pressure detection characteristics may be arranged along the wiring direction of the bit line BL (the y-axis direction in the drawing). As shown in FIG. You may arrange the pressure sensor 1 which has the same pressure detection characteristic along the wiring direction (x-axis direction in a figure) of the line WL. In the present embodiment, since it is a requirement that the plurality of pressure sensors 1 be two-dimensionally arranged so that the pressure sensors 1 having different pressure detection characteristics are adjacent to each other, further different third pressure detection characteristics. A pressure sensor 1 may be added to the array.

  The same applies to the pressure sensor group 1 including a plurality of pressure sensors 1. As shown in FIG. 6D, the pressure sensor group 1 of the present embodiment is composed of nine single pressure sensors 1 (see FIGS. 1 to 4). Each of the nine pressure sensors 1 may have the same pressure detection characteristics, or may have different pressure detection characteristics. However, the pressure sensor group 1A including nine pressure sensors 1 has a specific pressure detection characteristic as one pressure sensor group 1A. Similarly, a pressure sensor group 1B constituted by nine pressure sensors 1 has specific pressure detection characteristics different from the pressure sensor group 1A. The two pressure sensor groups 1 that are adjacent along either the word line WL or the bit line BL have different pressure detection characteristics. Specifically, in the present embodiment, as shown in FIG. 6D, the pressure sensor group 1 (1A) having one pressure detection characteristic as the aggregate of the pressure sensors 1 and the pressure sensor group 1 (1B) having another pressure detection characteristic. ) Are arranged alternately (in a staggered pattern). Of course, a pressure sensor group 1 having a third pressure detection characteristic that is different may be added to the array. FIG. 6D is an example of the arrangement of the pressure sensor group 1 corresponding to FIG. 6A, but the pressure sensor group 1 may be arranged in the manner shown in FIGS. 6B and 6C.

  The pressure sensor 1 having different pressure detection characteristics can be obtained by changing the pressure resistance characteristic of the pressure-sensitive conductor 20 described above. In the present embodiment, the pressure-sensitive conductor 20 of each pressure sensor 1 adjacent along either one of the word line WL or the bit line BL, or each adjacent along either one of the word line WL or the bit line BL. The pressure-sensitive conductor group 20 of the pressure sensor group 1 has different pressure resistance characteristics. In order to change the pressure resistance characteristic of the pressure-sensitive conductor 20 or the pressure-sensitive conductor group 20, in this embodiment, the composition of the material constituting the pressure-sensitive conductor 20 is changed or the sensitivity of the pressure-sensitive conductor 20 is changed. The composition of the material constituting the piezoelectric conductive layers 21 and 22 is changed. Of course, the pressure resistance characteristic of the pressure-sensitive conductor group 20 of each pressure sensor group 1 may be changed by changing the combination of the pressure-sensitive conductive layer 21 and the pressure-sensitive conductive layer 22 having different pressure resistance characteristics. .

  In the present embodiment, the pressure-sensitive conductors 20 of the pressure sensors 1 adjacent along either the word line WL or the bit line BL are formed using different pressure-sensitive conductive inks. The pressure-sensitive conductive ink that forms the pressure-sensitive conductor 20 may be a single type or a plurality of types. The types of single pressure-sensitive conductive inks used are not the same, or the types of the plurality of pressure-sensitive conductive inks used in combination need not be the same. For example, among the pressure-sensitive conductors 20 of the pressure sensors 1 adjacent to each other, one of the pressure-sensitive conductors 20 has a resistance change rate with respect to the pressure in the first pressure region described in FIG. The resistance change rate with respect to the pressure in the second pressure region is higher than the resistance change rate with respect to the pressure in the second pressure region, and the resistance change rate with respect to the pressure in the second pressure region is higher than the pressure in the second pressure region with respect to the pressure in the second pressure region. It is higher than the resistance change rate. The same applies to the pressure-sensitive conductor group 20. That is, among the pressure-sensitive conductor groups 20 of the pressure sensor groups 1 adjacent to each other, one of the pressure-sensitive conductor groups 20 has a resistance change rate with respect to the pressure in the first pressure region described in FIG. The resistance change rate with respect to the pressure in the second pressure region other than the region is higher, and the other pressure-sensitive conductor group 20 has a resistance change rate with respect to the pressure in the second pressure region. It is higher than the rate of change in resistance to pressure in the pressure region. In addition, in this specification, the 1st-4th pressure area | region which prescribes | regulates a pressure resistance characteristic, and its resistance change rate are each arbitrary values.

  As described above, when the pressure-sensitive conductor 20 includes a plurality of pressure-sensitive conductive layers such as the first pressure-sensitive conductive layer 21 and the second pressure-sensitive conductive layer 22, the pressure-sensitive conductive layer included in the pressure-sensitive conductor 20. Have different pressure resistance characteristics. In the case of forming one pressure-sensitive conductor 20, the types of the single pressure-sensitive conductive inks used for forming the pressure-sensitive conductive layer included therein are not the same or a plurality of pressure-sensitive conductors used in combination. The type and the mixing ratio of the characteristic inks are not necessarily the same. That is, the first pressure-sensitive conductive layer 21 has a resistance change rate with respect to pressure in a predetermined third pressure region higher than a resistance change rate with respect to pressure in a predetermined fourth pressure region other than the predetermined third pressure region. The resistance change rate with respect to the pressure in the predetermined fourth pressure region of the second pressure-sensitive conductive layer 22 is higher than the resistance change rate with respect to the pressure in the predetermined fourth pressure region of the first pressure-sensitive conductive layer 21. Here, the third pressure region corresponds to the first pressure region described in FIG. The third pressure region and the first pressure region may have the same region value or different region values. Similarly, the fourth pressure region corresponds to the second pressure region described in FIG. The fourth pressure region and the second pressure region may have the same region value or different region values.

  In addition to or instead of changing the pressure resistance characteristic of the pressure-sensitive conductor 20 as described above, the organic transistor 10 can be changed by changing the channel width or channel length between the source and drain of the pressure sensor 1. The pressure detection characteristic of the pressure sensor 1 may be changed by changing the resistance value.

  FIG. 7 is a diagram illustrating a state during a pressing operation of the pressure sensor module according to the embodiment of the present invention. As shown in FIG. 7, according to the pressure sensor module 100 of the present embodiment, a plurality of pressure sensors 1 having different pressure detection characteristics are arranged in a matrix so as to be adjacent to each other. The pressure corresponding to the input operation can be detected. When inputting with a human finger Fin or the like, the pressing force on the input surface is not constant, and the pressure value input by a partial region varies. In addition, in a pressing operation or the like while moving the finger Fin, the pressure value related to the input is likely to fluctuate, and the input value may become unstable. Even in such a case, in the present embodiment, since the pressure sensors 1 having different pressure detection characteristics are arranged in a matrix so as to be adjacent to each other, the pressure value that is input unevenly or the pressure value that fluctuates is high. It can be detected with accuracy.

  Hereinafter, based on FIGS. 8-15, the manufacturing method of the pressure sensor 1 of this embodiment is demonstrated.

  First, as shown in FIG. 8, the gate electrode 11 is formed on one main surface of the insulating substrate 2. As the insulating substrate 2, polymer films such as PET (polyethylene terephthalate), PEN (polyethylene naphthalate), and polyimide can be used. The formation method of the gate electrode 11 is not particularly limited, and the gate electrode 11 is formed by a printing technique such as an inkjet method or a gravure offset method, or a formation method such as vacuum deposition or a sputtering method. Examples of the material for the gate electrode 11 include metal nanoparticle inks such as Ag and Cu, and conductive polymers such as PEDOT (poly (3,4-ethylenedioxythiophene)) / PSS (polystyrene sulfonic acid). A metal material such as Au or Al can be used. After the gate electrode 11 is formed, baking is performed in an oven or the like as necessary.

  Next, as shown in FIG. 9, a gate insulating layer 14 for protecting the gate electrode 11 is formed. A film of an insulating material such as polyimide resin or PVP (polyvinylphenol) is formed using an inkjet printing method or a spin coating method. After applying the insulating material, the gate insulating layer 14 is formed by heating in an oven as necessary, followed by drying treatment and crosslinking treatment. The gate insulating layer 14 may be a single layer, or may be formed into a plurality of layers by repeatedly applying an insulating material, drying, and crosslinking.

  Next, as shown in FIG. 10, the source electrode 12 and the drain electrode 13 are formed. The formation method of the source electrode 12 and the drain electrode 13 is not particularly limited, and the source electrode 12 and the drain electrode 13 are formed by a printing technique such as an ink jet method or a gravure offset method, or a formation method such as vacuum deposition or a sputtering method. As a material of the source electrode 12 and the drain electrode 13, for example, a metal nanoparticle ink such as Ag or Cu, a conductive polymer such as PEDOT / PSS, or a metal material such as Au or Al can be used. After the source electrode 12 and the drain electrode 13 are formed, baking is performed in an oven or the like as necessary. In the present embodiment, the source electrode 12 is formed wide and extends to a region where the pressure-sensitive conductor 20 is disposed.

  Next, as shown in FIG. 11, the organic semiconductor layer 15 is formed. The method for forming the organic semiconductor layer 15 is not particularly limited, and for example, a printing technique such as an ink jet method or a flexographic printing method, or a film forming technique such as a vacuum evaporation method or a spray method can be used.

  In addition to pentacene, organic semiconductor materials include acenes such as anthracene, tetracene, and hexacene, or α-oligothiophenes such as quarterthiophene (4T), sexithiophene, octathiophene, DNTT (dinaphthothienothiophene). 1 type) or a mixture of two or more types of polycyclic aromatic hydrocarbon materials. In addition, poly (3-alkylthiophene), poly (3-hexylthiophene) (including poly (3-hexylthiophene-2,5-diyl): P3HT, PR-P3HT), poly (3-octylthiophene), poly ( 2,5-thienylene vinylene), poly (para-phenylene vinylene), poly (9,9-dioctylfluorene) ((Poly [(9,9-dioctylfluorenyl-2,7-diyl) -co-bithiophene]): F8 and F8T2), poly (9,9-dioctylfluorene-co-bis-N, N ′-(4-methoxyphenyl) -bis-N, N′-phenyl-1,4-phenylenediamine), poly (9,9-dioctylfluorene-co-benzothiadiazole), a non-charge-transfer fluorene copolymer (poly (9,9-dioctylfluorene-co-bithiophene)) and other organic semiconductor materials known at the time of filing this application Can be used.

  In this embodiment, since the pressure sensor 1 is produced using the organic semiconductor layer 15, it can be manufactured by a low temperature process. In addition, since a plastic substrate can be used, an element that is flexible and lightweight and is not easily broken can be provided. In addition, since the organic transistor 10 can be formed by a printing method, the manufacturing process can be greatly simplified as compared with the photolithography method for manufacturing the inorganic semiconductor layer, and the material used during the manufacturing is also greatly reduced. can do. For this reason, while reducing the environmental load at the time of manufacture, manufacturing cost can be suppressed.

  Next, as shown in FIG. 12, an insulating layer 17 covering the organic semiconductor layer 15 is formed. The material of the insulating layer 17 is not particularly limited, and for example, an insulating material such as parylene (paraxylylene-based polymer) or a fluorine-based insulating material can be used. In the present embodiment, CYTOP (registered trademark) manufactured by Asahi Kasei Corporation, which is an amorphous fluororesin, is used. Further, the formation method of the insulating layer 17 is not particularly limited, and the insulating layer 17 can be formed by a printing technique such as an inkjet method, a screen printing method, or a gravure offset method, or a forming method such as a vapor deposition method. The insulating layer 17 may have a multiple structure as necessary.

  Next, as shown in FIG. 13, a first pressure sensitive sensor is formed on the main surface of the source electrode 12 by screen printing using the above-described pressure sensitive conductive ink in a region where the organic semiconductor layer 15 is not formed. A conductive layer 21 is formed. The first pressure-sensitive conductive layer 21 can also be formed by sticking a thin pressure-sensitive conductive sheet.

  Next, as shown in FIG. 14, an insulating sheet having a thickness of about 50 to 100 μm, such as 50 μm in this example, is prepared as the cover member 50, and the second pad electrode 19 is provided on one main surface thereof. Form. Similar to the first pad electrode 18, the second pad electrode 19 is formed by a printing technique such as screen printing using a conductive ink containing a conductive material such as Ag, Cu, or Au, a vacuum deposition method, or a sputtering method. can do.

  Further, as shown in FIG. 15, the second pressure-sensitive conductive layer 22 is formed. In this example, the second pressure-sensitive conductive layer 22 is formed by screen printing using pressure-sensitive conductive ink so as to cover the second pad electrode 19. The pressure-sensitive conductive ink constituting the second pressure-sensitive conductive layer 22 may be the same as the pressure-sensitive conductive ink constituting the first pressure-sensitive conductive layer 21 or may be a different pressure-sensitive conductive ink. Also good. In addition, the type of the conductive particles and the elastic particles of the pressure-sensitive conductive ink that forms the second pressure-sensitive conductive layer 22 of this example, or the mixing ratio of the materials is the pressure-sensitive property that forms the first pressure-sensitive conductive layer 21. It is different from the kind of the conductive particles and elastic particles of the conductive ink or the mixing ratio of the materials. For this reason, the pressure resistance characteristic of the second pressure-sensitive conductive layer 22 formed in this example is different from the pressure resistance characteristic of the first pressure-sensitive conductive layer 21.

  Subsequently, a first opening 62A that is made of a polymer film such as PET or PEN and forms a first space 231 for housing the organic transistor 10 in the arrangement region of the organic transistor 10, and a first pressure-sensitive conductive material. The spacer 60 in which the layer 21, the second pressure-sensitive conductive layer 22, the first pad electrode 18 (source electrode 12), and the second opening 62B that forms the second space 232 for accommodating the second pad electrode 19 are formed. Is disposed on the gate insulating layer 14 with the adhesive layers 61a and 61b interposed therebetween. It is preferable that portions other than the first opening 62A and the second opening 62B have a solid structure or a structure (such as a honeycomb structure) that can maintain the space 23.

  Finally, the cover member 50 in which the second pad electrode 19 and the second pressure-sensitive conductive layer 22 shown in FIG. The first opening 62A and the second opening 62B formed by the spacer 60 are closed by the cover member 50, the first space 231 for accommodating the organic transistor 10, the first pressure-sensitive conductive layer 21, and the second sensitivity. A second space 232 that accommodates the piezoelectric conductive layer 22, the first pad electrode 18, and the second pad electrode 19 is formed (see FIGS. 2 and 3).

  Through the above steps, the pressure sensor 1 shown in FIG. 2 can be obtained. Further, a plurality of the obtained pressure sensors 1 are prepared, these are two-dimensionally arranged in the predetermined regions P and P1, and connected to the word lines WL and bit lines BL to produce the pressure sensor module 100 shown in FIG. To do.

  In addition, the material and manufacturing method for manufacturing the organic transistor 10 are not limited to the above, The material and manufacturing method known at the time of application can be applied suitably.

Second Embodiment
As described above, regarding this type of technology, a flexible detection device having a flexible structure in which a pressure sensor in which an organic transistor and a pressure-sensitive conductive rubber sheet are combined is arranged in a planar shape is known (Patent Document 1).

  However, since the surface pressure distribution detected by the pressure sensor module arranged in a plane is affected by the pressure resistance characteristics of the pressure-sensitive conductive rubber sheet and the input pressure value, the pressure resistance of the pressure-sensitive conductive rubber sheet When a pressing force in a pressure region with a small amount of change in characteristics is input, there is a problem that the accuracy of the detection result of the surface pressure distribution may be reduced.

  The problem to be solved by the present invention is to maintain or improve the detection accuracy of the surface pressure distribution regardless of the input pressing force.

  According to the pressure sensor module of the present embodiment, pressure sensors or pressure sensor groups having different pressure detection characteristics are arranged so as to be adjacent to each other, so that the resistance value change of the pressure sensitive conductor can be increased in a wide pressure region. it can. For this reason, even if the pressing force applied at the time of the input operation varies widely in the low pressure to high pressure region, the surface pressure distribution can be measured. As a result, it is possible to maintain or improve the measurement accuracy of the surface pressure distribution in a wide pressure region regardless of the pressing force applied during the input operation.

  Hereinafter, a pressure sensor module according to an embodiment of the present invention will be described with reference to the drawings. In this embodiment, a pressure sensor module in which pressure sensors are arranged in a matrix, and an example in which this is applied to a touch panel type input device will be described. In addition, in order to avoid redundant description, the description of the specification regarding the first embodiment and the description of the drawings are used for common points.

  The pressure sensor 1 of the present embodiment is arranged in a matrix along a predetermined operation surface that receives a pressing operation (touch operation), and constitutes a touch panel display. The application of the pressure sensor 1 of the present embodiment is not limited to a touch panel display, and can be applied to various sensors such as a fingerprint sensor and interfaces of various devices such as switches.

  The pressure sensor 1 of this embodiment is basically the same as the pressure sensor 1 described with reference to FIG. 1 in the first embodiment.

  Since the resistance value of the pressure-sensitive conductor 20 in the present embodiment changes according to the pressure received by pressing, the pressure-sensitive conductor 20 functions as a variable resistance member in the organic transistor 10 of the present embodiment. That is, when the resistance value of the pressure-sensitive conductor 20 decreases due to the pressure application, the potential difference between the source and the drain increases, and the amount of current flowing increases. By detecting this change in the amount of current, the amount of pressure applied to the pressure sensor 1 during the pressing operation can be detected.

  The pressure-sensitive conductor 20 of this embodiment is a pressure-sensitive conductive layer formed by printing using a pressure-sensitive conductive ink in which conductive particles and elastic particles are dispersed in a binder, and conductive particles and elastic particles are dispersed in the binder. A pressure-sensitive conductive layer formed by thinly forming a pressure-sensitive conductive material, and a pressure-sensitive conductive layer obtained by slicing a pressure-sensitive conductive sheet in which conductive particles and elastic particles are dispersed in a binder.

  Although it does not specifically limit, The material similar to 1st Embodiment can be used as electroconductive particle.

  FIG. 16 is a cross-sectional view of the pressure sensor 1 of the present embodiment having the circuit shown in FIG. As shown in FIG. 16, the gate electrode 11, the source electrode 12, and the drain electrode 13 constituting the organic transistor 10 are formed on one main surface side of the insulating substrate 2 and covered with the gate insulating layer 14. An organic semiconductor layer 15 is formed above 11 (upward in the drawing along the stacking direction, hereinafter the same). A pressure sensitive conductor 20 is formed on the organic semiconductor layer 15 via an insulating layer 17. Further, the upper surface of the pressure-sensitive conductor 20 (the upper surface in the drawing along the stacking direction, hereinafter the same) is covered with a cover member 50. In the pressure sensor 1 shown in FIG. 16, when the upper surface P of the cover member 50 is pressed, the organic transistor 10 outputs a signal corresponding to the pressing position and the pressing force.

  As shown in FIG. 16, the pressure-sensitive conductor 20 of the present embodiment has a first pressure-sensitive conductive layer 21 and a second pressure-sensitive conductive layer 22, and these first pressure-sensitive conductive layer 21 and second pressure-sensitive conductor. A space 23 is formed between the conductive layer 22 and the conductive layer 22. In the example shown in FIG. 16, one main surface 21 a of the first pressure-sensitive conductive layer 21 and one main surface 22 a of the second pressure-sensitive conductive layer 22 are surfaces to which a pressing force is applied along the arrow F direction in the drawing. Yes, both main surfaces 21a, 22a are arranged in parallel. Moreover, both the main surfaces 21a and 22a are arrange | positioned perpendicularly | vertically with respect to the direction (F direction in a figure) to which a pressing force is applied. Furthermore, the one principal surface 21 a of the first pressure-sensitive conductive layer 21 and the one principal surface 22 a of the second pressure-sensitive conductive layer 22 are disposed so as to face each other through the space 23. In the present embodiment, a spacer 60 is disposed between the insulating layer 17 and the cover member 50, and a space 23 is formed between the first pressure-sensitive conductive layer 21 and the second pressure-sensitive conductive layer 22 by the spacer 60. ing. As shown in the figure, the spacer 60 is arranged in parallel with the one principal surface 21 a of the first pressure-sensitive conductive layer 21 and the one principal surface 22 a of the second pressure-sensitive conductive layer 22.

  The spacer 60 of the present embodiment can be made of an insulating base material such as polyethylene terephthalate. The opening (the plane or bottom surface of the space 23) formed by the spacer 60 can be appropriately set according to the size of the operation switch. The spacer 60 of this example is fixed to the insulating layer 17 and the cover member 50 by adhesive layers 61a and 61b. The thickness of the spacer 60 including the adhesive layers 61a and 61b (the height of the space 23) can be 50 μm to 200 μm, preferably about 75 μm to 150 μm, and more preferably 100 μm or less. The thickness of the spacer 60 in this example is 75 μm or less. In the space 23 formed by the spacer 60 and the adhesive layers 61a and 61b, the first pad electrode 18, the second pad electrode 19, the first pressure-sensitive conductive layer 21, and the second pressure-sensitive conductive layer 22 are formed. The distance between the first pressure-sensitive conductive layer 21 and the second pressure-sensitive conductive layer 22 in this example is about 30 μm. The distance between the first pressure-sensitive conductive layer 21 and the second pressure-sensitive conductive layer 22 is not particularly limited, and the thickness of the insulating layer 17, the thickness of the cover member 50, the first pressure-sensitive conductive layer 21, and the second pressure-sensitive conductive layer. Considering factors such as the thickness of the conductive layer 22, the thickness of the spacer 60, the pressure resistance characteristics of the pressure-sensitive conductive layers 21 and 22, the magnitude of the pressing force applied during the pressing operation, and the threshold value for on / off identification Thus, it can be set appropriately based on experiments. The space 23 is not limited between the first pressure-sensitive conductive layer 21 and the second pressure-sensitive conductive layer 22 depending on the configuration of the pressure sensor 1, and the first pressure-sensitive conductive layer 21, the first pad electrode 18, and the like. Or between the second pressure-sensitive conductive layer 22 and the second pad electrode 19.

  When the user performs a pressing operation and the cover member 50 is pressed along the direction of arrow F in FIG. 16, the one principal surface 21 a of the first pressure-sensitive conductive layer 21 and the one principal surface 22 a of the second pressure-sensitive conductive layer 22. Since a pressing force in the direction of arrow F is applied to the second pressure-sensitive conductive layer 22, the second pressure-sensitive conductive layer 22 arranged on the cover member 50 side moves in the space 23 to the insulating layer 17 side. When the second pressure-sensitive conductive layer 22 contacts the first pressure-sensitive conductive layer 21, the first pressure-sensitive conductive layer 21 and the second pressure-sensitive conductive layer 22 are electrically connected in series and are in a conductive state (ON State). On the other hand, when the applied pressing force is released, the second pressure-sensitive conductive layer 22 is separated from the first pressure-sensitive conductive layer 21 and moves in the space 23 toward the cover member 50. Thus, the space 23 formed between the first pressure-sensitive conductive layer 21 and the second pressure-sensitive conductive layer 22 becomes a movable region of the first pressure-sensitive conductive layer 21 and the second pressure-sensitive conductive layer 22. Therefore, the first pressure-sensitive conductive layer 21 can be brought into contact with or separated from the second pressure-sensitive conductive layer 22 in accordance with the pressing operation. In order to bring the first pressure-sensitive conductive layer 21 into contact with the second pressure-sensitive conductive layer 22, it is necessary to apply a pressing force for moving the second pressure-sensitive conductive layer 22 by a distance corresponding to the thickness of the space 23. is there. The first pressure-sensitive conductive layer 21 and the second pressure-sensitive conductive layer can be brought into contact with the second pressure-sensitive conductive layer 22 when a pressing force of a predetermined value or more is applied. The ON state due to the contact of 22 and the OFF state due to the separation between the first pressure-sensitive conductive layer 21 and the second pressure-sensitive conductive layer 22 can be clearly distinguished.

  By forming the space 23 with the spacer 60, the on / off recognition sensitivity according to the pressing operation can be improved as in the first embodiment.

  The pressure sensor 1 of the present embodiment includes a first pad electrode 18 that can contact or contact the first pressure-sensitive conductive layer 21, and a second pad electrode 19 that can contact or contact the second pressure-sensitive conductive layer 22. Further, the first pad electrode 18 is electrically connected to either the source electrode 12 or the voltage power supply 30, and the second pad electrode 19 is electrically connected to either the source electrode 12 or the voltage power supply 30. It can be configured to be connected.

  In the example shown in FIG. 16, the lower surface side of the first pressure-sensitive conductive layer 21 arranged on the lower side of the pressure-sensitive conductor 20 of the present embodiment, that is, the insulating layer 17 and the first pressure-sensitive conductive layer 21. A first pad electrode 18 is formed between them. The first pressure-sensitive conductive layer 21 (pressure-sensitive conductor 20) is electrically connected in series with the source electrode 12 through the first pad electrode 18 and the first pad electrode via 18a connected thereto. Further, as shown in the figure, the upper surface side of the second pressure-sensitive conductive layer 22 disposed on the upper side of the pressure-sensitive conductor 20, that is, between the cover member 50 and the second pressure-sensitive conductive layer 22. A second pad electrode 19 is formed. The second pressure-sensitive conductive layer 22 is electrically connected to the voltage power supply 30 through the second pad electrode 19. The second pad electrode 19 and the first pad electrode 18 connected to the voltage power source 30 can be conducted through the pressure-sensitive conductor 20 (pressure-sensitive conductive layers 21 and 22).

  FIG. 16 shows an example in which the first pressure-sensitive conductive layer 21 is disposed below the second pressure-sensitive conductive layer 22, but the second pressure-sensitive conductive layer 22 is disposed on the lower side, that is, on the insulating layer 17 side. It can also be arranged.

  In the present embodiment, the first pressure-sensitive conductive layer 21 and the second pressure-sensitive conductive layer 22 constituting the pressure-sensitive conductor 20 can be configured to have different pressure resistance characteristics. The pressure resistance characteristic of the present embodiment is a mode of change in resistance value with respect to an applied pressure value at the time of pressing. The pressure resistance characteristic can be evaluated based on a resistance value in a region of a predetermined applied pressure value, a change amount of the resistance value, and the like.

  The reason why the pressure-sensitive conductive layers 21 and 22 having different pressure resistance characteristics are electrically connected in series is the same as the reason described in the first embodiment.

  Further, the technique for adjusting the pressure resistance characteristics of the pressure sensitive conductor 20 (pressure sensitive conductive layers 21 and 22) (the technique for obtaining the pressure sensitive conductor 20 having an arbitrary pressure resistance characteristic) is the same technique as in the first embodiment. Can be used.

  In this manner, the pressure-sensitive conductive layer 21 having a high resistance change rate in a region having a relatively low pressure value can be electrically connected to the pressure-sensitive conductive layer 22 having a high resistance change rate in a region having a medium to high pressure value. The pressure-sensitive conductor 20 is configured in such a manner that it is electrically inserted in series between the voltage power source 30 and the source electrode 12 of the organic transistor 10 to cause a large resistance change in a wide pressure region. Therefore, the potential difference between the source and the drain also increases, and as a result, the pressure sensor 1 having high sensitivity in a wide pressure region can be provided.

  Next, the pressure sensor module 100 will be described. FIG. 5 is a circuit diagram of a pressure sensor module in which a plurality of pressure sensors 1 having the above-described configuration are prepared and arranged two-dimensionally at predetermined pitches in the vertical and horizontal directions (along the xy axes). As shown in FIG. 5, the pressure sensors 1 are arranged in a predetermined region P. A word line WL and a bit line BL are wired along the arrangement direction (xy axis direction) of the pressure sensors 1 in the predetermined region P. In this example, the word lines WL are wired along the x-axis direction, and the bit lines BL are wired along the y-axis direction. The organic transistor 10 sends the detected signal and its own address signal to the signal processing device 40 via the word line WL and the bit line BL.

  The pressure sensor module 100 of the present embodiment is configured by two-dimensionally arranging pressure sensors 1 having different pressure detection characteristics. The pressure detection characteristic here includes the detection characteristic for the pressure described above. In the present embodiment, the pressure detection characteristic of the pressure sensor 1 can be changed by changing the pressure resistance characteristic of the pressure-sensitive conductor 20 or by changing the pressure resistance characteristic of the pressure-sensitive conductive layers 21 and 22. .

  Specifically, in the pressure sensor module 100 according to the present embodiment, two pressure sensors 1 adjacent along either the word line WL or the bit line BL are two-dimensionally arranged to have different pressure detection characteristics. It is arranged.

  Also in this embodiment, the pressure sensors 1 can be arranged in the manner of FIGS. 6A to 6D, as in the first embodiment.

  Pressure sensors 1 having different pressure detection characteristics can be obtained by changing the pressure resistance characteristics of the pressure-sensitive conductor 20 described above. In the present embodiment, the pressure-sensitive conductor 20 of each pressure sensor 1 adjacent along either one of the word line WL or the bit line BL, or each adjacent along either one of the word line WL or the bit line BL. The pressure-sensitive conductor group 20 of the pressure sensor group 1 has different pressure resistance characteristics. In order to change the pressure resistance characteristic of the pressure-sensitive conductor 20 or the pressure-sensitive conductor group 20, in this embodiment, the composition of the material constituting the pressure-sensitive conductor 20 is changed or the sensitivity of the pressure-sensitive conductor 20 is changed. The composition of the material constituting the piezoelectric conductive layers 21 and 22 is changed. Of course, the pressure resistance characteristic of the pressure-sensitive conductor group 20 of each pressure sensor group 1 may be changed by changing the combination of the pressure-sensitive conductive layer 21 and the pressure-sensitive conductive layer 22 having different pressure resistance characteristics. .

  In the present embodiment, the pressure-sensitive conductors 20 of the pressure sensors 1 adjacent along either the word line WL or the bit line BL are formed using different pressure-sensitive conductive inks. The pressure-sensitive conductive ink that forms the pressure-sensitive conductor 20 may be a single type or a plurality of types. The types of single pressure-sensitive conductive inks used are not the same, or the types of the plurality of pressure-sensitive conductive inks used in combination need not be the same. For example, among the pressure-sensitive conductors 20 of the pressure sensors 1 adjacent to each other, one of the pressure-sensitive conductors 20 has a resistance change rate with respect to the pressure in the first pressure region described in FIG. The resistance change rate with respect to the pressure in the second pressure region is higher than the resistance change rate with respect to the pressure in the second pressure region, and the resistance change rate with respect to the pressure in the second pressure region is higher than the pressure in the second pressure region with respect to the pressure in the second pressure region. It is higher than the resistance change rate. The same applies to the pressure-sensitive conductor group 20. That is, among the pressure-sensitive conductor groups 20 of the pressure sensor groups 1 adjacent to each other, one of the pressure-sensitive conductor groups 20 has a resistance change rate with respect to the pressure in the first pressure region described in FIG. The resistance change rate with respect to the pressure in the second pressure region other than the region is higher, and the other pressure-sensitive conductor group 20 has a resistance change rate with respect to the pressure in the second pressure region. It is higher than the rate of change in resistance to pressure in the pressure region. In addition, in this specification, the 1st-4th pressure area | region which prescribes | regulates a pressure resistance characteristic, and its resistance change rate are each arbitrary values.

  As described above, when the pressure-sensitive conductor 20 includes a plurality of pressure-sensitive conductive layers such as the first pressure-sensitive conductive layer 21 and the second pressure-sensitive conductive layer 22, the pressure-sensitive conductive layer included in the pressure-sensitive conductor 20. Have different pressure resistance characteristics. In the case of forming one pressure-sensitive conductor 20, the types of the single pressure-sensitive conductive inks used for forming the pressure-sensitive conductive layer included therein are not the same or a plurality of pressure-sensitive conductors used in combination. The types of the characteristic inks may not be the same. That is, the first pressure-sensitive conductive layer 21 has a resistance change rate with respect to pressure in a predetermined third pressure region higher than a resistance change rate with respect to pressure in a predetermined fourth pressure region other than the predetermined third pressure region. The resistance change rate with respect to the pressure in the predetermined fourth pressure region of the second pressure-sensitive conductive layer 22 is higher than the resistance change rate with respect to the pressure in the predetermined fourth pressure region of the first pressure-sensitive conductive layer 21. Here, the third pressure region corresponds to the first pressure region described in FIG. The third pressure region and the first pressure region may have the same region value or different region values. Similarly, the fourth pressure region corresponds to the second pressure region described in FIG. The fourth pressure region and the second pressure region may have the same region value or different region values.

  The same applies to the pressure sensor group 1. Each pressure sensor group 1 adjacent along either the word line WL or the bit line BL is formed using different pressure-sensitive conductive inks or different combinations of pressure-sensitive conductive inks.

  In addition to or instead of changing the pressure resistance characteristic of the pressure-sensitive conductor 20 as described above, the organic transistor 10 can be changed by changing the channel width or channel length between the source and drain of the pressure sensor 1. The pressure detection characteristic of the pressure sensor 1 may be changed by changing the resistance value.

  FIG. 17 is a diagram illustrating a state during the pressing operation of the pressure sensor module according to the embodiment of the present invention. As shown in FIG. 17, according to the pressure sensor module 100 of the present embodiment, a plurality of pressure sensors 1 having different pressure detection characteristics are arranged in a matrix so as to be adjacent to each other. The pressure corresponding to the input operation can be detected. When inputting with a human finger Fin or the like, the pressing force on the input surface is not constant, and the pressure value input by a partial region varies. In addition, in a pressing operation or the like while moving the finger Fin, the pressure value related to the input is likely to fluctuate, and the input value may become unstable. Even in such a case, in the present embodiment, since the pressure sensors 1 having different pressure detection characteristics are arranged in a matrix so as to be adjacent to each other, the pressure value that is input unevenly or the pressure value that fluctuates is high. It can be detected with accuracy.

  Hereinafter, based on FIGS. 18-26, the manufacturing method of the pressure sensor 1 of this embodiment is demonstrated.

  First, as shown in FIG. 18, the gate electrode 11 is formed on one main surface of the insulating substrate 2. As the insulating substrate 2, polymer films such as PET (polyethylene terephthalate), PEN (polyethylene naphthalate), and polyimide can be used. The formation method of the gate electrode 11 is not particularly limited, and the gate electrode 11 is formed by a printing technique such as an inkjet method or a gravure offset method, or a formation method such as vacuum deposition or a sputtering method. Examples of the material for the gate electrode 11 include metal nanoparticle inks such as Ag and Cu, and conductive polymers such as PEDOT (poly (3,4-ethylenedioxythiophene)) / PSS (polystyrene sulfonic acid). A metal material such as Au or Al can be used. After the gate electrode 11 is formed, baking is performed in an oven or the like as necessary.

  Next, as shown in FIG. 19, an insulating layer 16 that functions as a bank (weir) is formed around the gate electrode 11 using a resin material such as an epoxy resin by a method such as screen printing. After forming the insulating layer 16, it is dried in an oven or the like as necessary. Note that the insulating layer 16 of this example is not necessarily required, and may be formed according to a later process or a material used in a later process. Subsequently, the gate insulating layer 14 is formed so as to cover the gate electrode 11 using a resin material such as a polyimide resin, for example, using a printing technique such as an inkjet method. After the insulating layer 14 is formed, it is heated in an oven or the like as necessary to perform drying and crosslinking.

  Next, as shown in FIG. 20, the source electrode 12 and the drain electrode 13 are formed. The formation method of the source electrode 12 and the drain electrode 13 is not particularly limited, and the source electrode 12 and the drain electrode 13 are formed by a printing technique such as an ink jet method or a gravure offset method, or a formation method such as vacuum deposition or a sputtering method. As a material of the source electrode 12 and the drain electrode 13, for example, a metal nanoparticle ink such as Ag or Cu, a conductive polymer such as PEDOT / PSS, or a metal material such as Au or Al can be used. After the source electrode 12 and the drain electrode 13 are formed, baking is performed in an oven or the like as necessary.

  Next, as shown in FIG. 21, the organic semiconductor layer 15 is formed. The formation method of the organic semiconductor layer 15 is not particularly limited, and for example, a printing technique such as an inkjet method or a flexographic printing method, or a film forming method such as a vacuum evaporation method or a spray method can be used. Further, as the organic semiconductor material, the same material as that of the first embodiment can be used.

  In this embodiment, since the pressure sensor 1 is produced using the organic semiconductor layer 15, it can be manufactured by a low temperature process. In addition, since a plastic substrate can be used, an element that is flexible and lightweight and is not easily broken can be provided. In addition, since the organic transistor 10 can be formed by a printing method, the manufacturing process can be greatly simplified as compared with the photolithography method for manufacturing the inorganic semiconductor layer, and the material used during the manufacturing is also greatly reduced. can do. For this reason, while reducing the environmental load at the time of manufacture, manufacturing cost can be suppressed.

Next, as shown in FIG. 22, an insulating layer 17 that covers the organic semiconductor layer 15 is formed. The material of the insulating layer 17 is not particularly limited, and for example, an insulating material such as parylene (paraxylylene-based polymer) or a fluorine-based insulating material can be used. In the present embodiment, CYTOP (registered trademark) manufactured by Asahi Kasei Corporation, which is an amorphous fluororesin, is used. Further, the formation method of the insulating layer 17 is not particularly limited, and the insulating layer 17 can be formed by a printing technique such as an inkjet method, a screen printing method, or a gravure offset method, or a forming method such as a vapor deposition method. The insulating layer 17 may have a multiple structure as necessary. Further, as shown in the figure, the insulating layer 17 is formed with a via hole 18a ′ for a via 18a that constitutes a part of the first pad electrode 18 that is electrically connected to the source electrode 12 in the product. A method for forming the via hole 18a ′ is not particularly limited. In this example, the via hole 18a ′ is formed by drilling with a CO ₂ laser.

  Next, as shown in FIG. 23, the via hole 18 a ′ formed in the previous step is filled with a conductive material to form the first pad electrode 18 that is electrically connected to the source electrode 12. The conductive material used for forming the first pad electrode 18 is not particularly limited, but a metal material such as Au or Ag, or a conductive paste containing these materials can be used. The formation method of the first pad electrode 18 is not particularly limited, and a printing technique such as an ink jet method or a screen printing method, or a film forming method such as a vacuum evaporation method or a sputtering method can be used. Further, an insulating layer 17 in which a first pad electrode 18 including a via 18a and an electrode is formed in advance is prepared, and this insulating layer 17 is laminated on a semi-finished product on which the organic semiconductor layer 15 shown in FIG. 21 is formed. Thus, the semi-finished product shown in FIG. 23 can be obtained.

  As shown in FIG. 24, a first pressure-sensitive conductive layer 21 is formed by screen printing using pressure-sensitive conductive ink so as to be in contact with the first pad electrode 18. The first pressure-sensitive conductive layer 21 can also be formed by sticking a thin pressure-sensitive conductive sheet.

  Next, as shown in FIG. 25, an insulating sheet having a thickness of about 50 to 100 μm such as PET or PEN is prepared as the cover member 50, and the second pad electrode 19 is formed on one main surface thereof. Similar to the first pad electrode 18, the second pad electrode 19 is formed by a printing technique such as screen printing using a conductive ink containing a conductive material such as Ag, Cu, or Au, a vacuum deposition method, or a sputtering method. can do.

  Further, as shown in FIG. 26, the second pressure-sensitive conductive layer 22 is formed. In this example, the second pressure-sensitive conductive layer 22 is formed by screen printing using pressure-sensitive conductive ink so as to cover the second pad electrode 19. The pressure-sensitive conductive ink constituting the second pressure-sensitive conductive layer 22 may be the same as the pressure-sensitive conductive ink constituting the first pressure-sensitive conductive layer 21 or may be a different pressure-sensitive conductive ink. Also good. In addition, the type of the conductive particles and the elastic particles of the pressure-sensitive conductive ink that forms the second pressure-sensitive conductive layer 22 of this example, or the mixing ratio of the materials is the pressure-sensitive property that forms the first pressure-sensitive conductive layer 21. It is different from the kind of the conductive particles and elastic particles of the conductive ink or the mixing ratio of the materials. For this reason, the pressure resistance characteristic of the second pressure-sensitive conductive layer 22 formed in this example is different from the pressure resistance characteristic of the first pressure-sensitive conductive layer 21.

  Subsequently, the opening 23 is formed of a polymer film such as PET or PEN and accommodates the first pressure-sensitive conductive layer 21, the second pressure-sensitive conductive layer 22, the first pad electrode 18, and the second pad electrode 19. The spacer 60 formed with is disposed on the insulating layer 17 with the adhesive layers 61a and 61b interposed therebetween.

  Finally, the cover member 50 in which the second pad electrode 19 and the second pressure-sensitive conductive layer 22 shown in FIG. 26 are formed on the spacer 60 is disposed. The opening 23 formed by the spacer 60 is closed by the cover member 50, and a space 23 for accommodating the first pressure-sensitive conductive layer 21, the second pressure-sensitive conductive layer 22, the first pad electrode 18, and the second pad electrode 19 is formed. Formed (see FIG. 16). Further, the arrangement of the first pressure-sensitive conductive layer 21 and the second pressure-sensitive conductive layer 22 is not particularly limited, and any one of the pressure-sensitive conductive layers 21 and 22 is on the cover member 50 side (upper side in the figure) or the insulating substrate 2. It may be arranged on the side (lower side in the figure).

  Through the above steps, the pressure sensor 1 shown in FIG. 16 can be obtained. Further, a plurality of obtained pressure sensors 1 are prepared, these are two-dimensionally arranged in the predetermined regions P and P1, and connected to the word line WL and the bit line BL, as shown in FIGS. 5 and 6A to 6D. The pressure sensor module 100 is produced.

  FIG. 27, FIG. 28, FIG. 2, and FIG. 29 are diagrams showing another configuration example of the pressure sensor 1 of the present embodiment. Since the connection relationship between the pressure sensor 1 and the voltage power source shown in each drawing is the same as that of the pressure sensor 1 of this embodiment, the illustration is omitted in the drawing.

  The pressure sensor 1 shown in FIGS. 27 and 28 will be described. In the pressure sensor 1 of the present example, the first pressure-sensitive conductive layer 21 and the second pressure-sensitive conductive layer 22 to which pressure is applied are arranged so that their respective principal surfaces are parallel to each other, and the arrow F in the figure indicates They can be electrically connected in series according to a pressing operation in which a pressing force is applied along the direction. In the example shown in the figure, the first pressure-sensitive conductive layer 21 and the second pressure-sensitive conductive layer 22 are in the xy coordinate plane along the main surface of the first pressure-sensitive conductive layer 21 or the second pressure-sensitive conductive layer 22. They are arranged at different positions on the top. That is, the first pressure-sensitive conductive layer 21 and the second pressure-sensitive conductive layer 22 are not arranged so as to face each other as in the pressure sensor 1 shown in FIG. The two pressure-sensitive conductive layers 22 are arranged in parallel (so as not to overlap) on a plane parallel to the main surface of the insulating layer 17.

  The pressure sensor 1 shown in FIGS. 27 and 28 includes a first pad electrode 18 that can contact or contact the first pressure-sensitive conductive layer 21 and a second pad that can contact or contact the second pressure-sensitive conductive layer 22. And an electrode 19. The first pad electrode 18 and the second pad electrode 19 are arranged in parallel at different positions on the xy coordinate plane along one main surface of the first pressure-sensitive conductive layer 21. The first pad electrode 18 is electrically connected to either the source electrode 12 or the voltage power supply 30, and the second pad electrode 19 is electrically connected to either the source electrode 12 or the voltage power supply 30. Is done.

  Specifically, in the pressure sensor 1 shown in FIG. 27, the first pressure-sensitive conductive layer 21 arranged in parallel with the second pressure-sensitive conductive layer 22 on the insulating layer 17 side is in contact with the first pad electrode 18. The source electrode 12 is electrically connected through the first pad electrode 18. On the other hand, the second pressure-sensitive conductive layer 22 provided on the insulating layer 17 side is disposed so as to face the second pad electrode 19 provided on the cover member 50 side, and the cover member 50 is pressed in the direction of arrow F. Then, they approach each other and the second pressure-sensitive conductive layer 22 and the second pad electrode 19 are electrically connected. Thus, during the pressing operation, the first pad electrode 18, the first pressure-sensitive conductive layer 21, the second pressure-sensitive conductive layer 22, and the second pad electrode 19 are electrically connected in series. In addition, although illustration is abbreviate | omitted, in this example, the 2nd pad electrode 19 is electrically connected with the voltage power supply 30 outside a figure.

  As shown in FIG. 27, the first pressure-sensitive conductive layer 21 and the second pressure-sensitive conductive layer 22 are arranged in parallel at different positions on the insulating layer 17 side, and the first pressure-sensitive conductive layer arranged in parallel is arranged. A wiring 70 is formed to electrically connect the conductive layer 21 and the second pressure-sensitive conductive layer 22 in series. The wiring 70 can be formed by screen printing using a conductive paste after curing a pressure-sensitive conductive ink layer obtained by screen-printing the first pressure-sensitive conductive layer 21 and the second pressure-sensitive conductive layer 22. . In the example shown in FIG. 27, an example is shown in which the first pressure-sensitive conductive layer 21 is arranged on the right side in the drawing and the second pressure-sensitive conductive layer 22 is arranged on the left side in the drawing. The pressure conductive layer 21 may be disposed, and the second pressure sensitive conductive layer 22 may be disposed on the right side in the drawing.

  As another example, in the pressure sensor 1 shown in FIG. 28, the first pressure-sensitive conductive layer 21 and the second pressure-sensitive conductive layer 22 are arranged in parallel at different positions on the cover member 50 side. As shown in the figure, the second pad electrode 19 is formed on the main surface of the cover member 50, and the second pressure-sensitive conductive layer 22 in contact with the second pad electrode 19 is formed on the cover member 50 side. . Further, a wiring 70 that electrically connects the second pressure-sensitive conductive layer 22 and the first pressure-sensitive conductive layer 21 in series is formed, and the first pressure-sensitive conductive layer 21 that is in contact with the wiring 70 is the cover member 50. Formed on the side. The first pressure-sensitive conductive layer 21 is disposed so as to face the first pad electrode 18 provided on the insulating layer 17 side. When the cover member 50 is pressed in the direction of arrow F, the first pressure-sensitive conductive layer 21 approaches each other. The pressure sensitive conductive layer 21 and the first pad electrode 18 are electrically connected. Thus, during the pressing operation, the first pad electrode 18, the first pressure-sensitive conductive layer 21, the second pressure-sensitive conductive layer 22, and the second pad electrode 19 are electrically connected in series. In addition, although illustration is abbreviate | omitted, in this example, the 2nd pad electrode 19 is electrically connected with the voltage power supply 30 outside a figure.

  Further, the pressure sensor 1 shown in FIG. 28 forms the second pad electrode 19 on the main surface of the cover member 50 by screen printing / curing the conductive paste, and screen printing / curing the pressure-sensitive conductive paste. Thus, the second pressure-sensitive conductive layer 22 is formed, and the wiring 70 is formed by screen printing / curing the conductive paste, and then the first pressure-sensitive conductive material is screen-printing / curing the pressure-sensitive conductive paste. It is obtained by forming the layer 21. In the example shown in FIG. 28, the first pressure-sensitive conductive layer 21 is arranged on the right side in the figure, and the second pressure-sensitive conductive layer 22 is arranged on the left side in the figure. The pressure conductive layer 21 may be disposed, and the second pressure sensitive conductive layer 22 may be disposed on the right side in the drawing.

  27 and 28, the first pressure-sensitive conductive layer 21 and the second pressure-sensitive conductive layer 22 are arranged to face each other by arranging the first pressure-sensitive conductive layer 21 and the second pressure-sensitive conductive layer 22 in parallel. Rather than doing so, the thickness of the spacer 60 can be reduced, or the height of the space 23 can be reduced. As a result, the pressure sensor 1 can be further reduced in height. FIG. 27 shows an example of the pressure sensor 1 in which a space 23 is provided between the second pressure-sensitive conductive layer 22 and the second pad electrode 19, and FIG. 28 shows the first pressure-sensitive conductive layer 21 and the first pressure-sensitive conductive layer 21. An example in which a space 23 is formed between one pad electrode 18 is shown.

  Further, the first pressure-sensitive conductive layer 21 and the first pad electrode 18 are arranged at positions where they can contact or contact each other, and the second pressure-sensitive conductive layer 22 and the second pad electrode 19 are contacted or contacted with each other. By arranging at a possible position, the first pressure-sensitive conductive layer 21 and the second pressure-sensitive conductive layer 22 having elasticity and the first pad electrode 18 and the second pad electrode 19 having relatively high hardness are provided during the pressing operation. Can be brought into contact (contact) with each other, so that an electrical connection corresponding to the pressing operation can be achieved and the contact property can be improved. As a result, it is possible to provide the pressure sensor 1 having good responsiveness to the pressing operation.

  2 and 29 show still another configuration example of the pressure sensor 1. FIG. As shown in the figure, in the pressure sensor 1 of the present embodiment, the organic semiconductor layer 15, the gate electrode 11, the source electrode 12, and the drain electrode 13 (organic transistor 10) are disposed on the main surface side of the insulating substrate 2. And the first pressure-sensitive conductive layer 21 of the pressure-sensitive conductor 20 are formed in different regions. That is, as shown in the figure, on the xy coordinate plane parallel to the main surface of the pressure-sensitive conductor 20, the pressure-sensitive conductor 20 (the first pressure-sensitive conductive layer 21 and the second pressure-sensitive conductive layer 22) and the organic The transistors 10 (the organic semiconductor layer 15, the gate electrode 11, the source electrode 12, and the drain electrode 13) are arranged in parallel at different positions without overlapping.

  As described above, the organic transistor 10 and the pressure-sensitive conductor 20 are arranged in parallel so as not to overlap with each other, so that the pressure sensor 1 can be thinned. Further, when the pressure-sensitive conductor 20 and the organic transistor 10 are configured to overlap each other, there is a disadvantage that the pressing force is also applied to the organic transistor 10 when the pressing force is applied to the pressure-sensitive conductor 20. However, such inconvenience can be eliminated by arranging them in parallel as in the present embodiment.

  Although not particularly limited, in the pressure sensor 1 of the present embodiment, the height position of the installation surface of the pressure-sensitive conductor 20 and the organic transistor in the thickness direction of the pressure sensor 1 parallel to the thickness direction of the insulating substrate 2. 10 is configured such that the difference from the height position of the installation surface is less than a predetermined value. Specifically, the height of the installation surface with respect to the insulating substrate 2 in any one of the members of the organic semiconductor layer 15, the gate electrode 11, the source electrode 12, and the drain electrode 13 constituting the organic transistor 10; The height difference between the pressure-sensitive conductor 20 and the height of the installation surface with respect to the insulating base material 2 is configured to be less than a predetermined value. Of course, another member is interposed between the insulating base material 2, that is, another member is laminated on the insulating base material 2, and the organic transistor 10 (including constituent members) is formed on the other member. And the aspect in which the pressure-sensitive conductor 20 was installed is also included.

  In the example shown in the figure, the organic transistor 10 of the present embodiment has a gate insulating layer in which the lowest part (a part on the lower side in the figure) of the organic semiconductor layer 15 which is one of the members constituting the organic transistor 10 It is installed on the upper side of the insulating base material 2 in a state of being in contact with the upper surface (main surface) of 14. The height of the organic transistor when the main surface of the insulating base material 2 is used as a reference is d1. Further, the pressure-sensitive conductor 20 of the present embodiment has a first pressure-sensitive conductive layer 21 on the electrode (source electrode 12, first pad electrode 18) (main surface) formed on the gate insulating layer 14. It is installed in contact. The height of the first pressure-sensitive conductive layer 21 when the main surface of the insulating substrate 2 is used as a reference is d2. The height position d1 of the installation surface of the organic transistor 10 (including the organic semiconductor layer 15 and other members constituting the organic transistor 10, the same applies hereinafter) and the height position d2 of the installation surface of the first pressure-sensitive conductive layer 21 The difference is d. The pressure sensor 1 of the present embodiment is characterized in that the height difference d is less than a predetermined value. From the viewpoint of reducing the thickness of the pressure sensor 1, the height difference d can be set by multiplying the thickness of the pressure sensor 1 by a predetermined ratio. Alternatively, the pressure sensor 1 can be set by multiplying the thickness of the insulating base material 2 that is a thick member by a predetermined ratio.

  In addition, the content that the height position difference (height difference) is less than a predetermined value includes the case where the height difference is zero, that is, the organic transistor 10 (including the organic semiconductor layer 15 and other members constituting the organic transistor 10) And the case where at least a part of the installation surface of the same) and at least a part of the installation surface of the pressure-sensitive conductor 20 are formed on an xy coordinate plane parallel to the main surface of the insulating substrate 2. In the pressure sensor 1 of the present embodiment shown in FIG. 2, the bottom surface (installation surface) of the organic semiconductor layer 15 of the organic transistor 10 is the main surface of the gate insulating layer 14, the main surface above the drain electrode 13, and the source electrode 12. It is in contact with the upper main surface. The bottom surface (installation surface) of the first pressure-sensitive conductive layer 21 is in contact with the upper main surface of the source electrode 12. That is, when the upper main surface of the source electrode 12 formed on the main surface of the insulating substrate 2 (xy coordinate plane parallel to the main surface of the insulating substrate 2) is used as a reference, the bottom surface of the organic semiconductor layer 15 The height of a part of the (installation surface) and the height of a part of the bottom surface (installation surface) of the first pressure-sensitive conductive layer 21 are the same, and the height difference is zero. In addition, when the first pressure-sensitive conductive layer 21 is not formed on the first pad electrode 18 but is formed directly on the upper main surface of the gate insulating layer 14 in contact with the side surface of the source electrode 12, an insulating substrate is formed. The height of the installation surface of the organic transistor 10 with respect to the main surface of the material 2 and the height of the installation surface of the first pressure-sensitive conductive layer 21 are the same, and the height difference is zero. In this case, wiring for connecting the first pressure-sensitive conductive layer 21 or the second pressure-sensitive conductive layer 22 and the source electrode 12 is appropriately provided.

  As described above, the organic transistor 10 and the pressure-sensitive conductor 20 are arranged in parallel so as not to overlap each other, and the height of the installation surface of the organic transistor 10 and the pressure-sensitive conductor 20 is made less than a predetermined value. Thus, the pressure sensor 1 can be further reduced in thickness.

  In addition, the material and manufacturing method for manufacturing the organic transistor 10 are not limited to the above, The material and manufacturing method known at the time of application can be applied suitably.

  As described above, in the present invention, the pressure sensor module 100 according to the present embodiment arranges the pressure sensors 1 having different pressure detection characteristics so as to be adjacent to each other, so that the potential difference between the source and the drain with respect to a wide range of pressing force is reduced. The amount of fluctuation can be increased. As a result, it is possible to provide the pressure sensor 1 (touch panel display) with good sensitivity regardless of the strength of the pressing force.

<Third Embodiment>
As described above, regarding this type of technology, a flexible detection device having a flexible structure in which a pressure sensor in which an organic transistor and a pressure-sensitive conductive rubber sheet are combined is arranged in a planar shape is known (Patent Document 1). In general, since the on-resistance of an organic transistor is as high as MΩ order, in order to vary the potential difference between the source and drain, the resistance change of the pressure-sensitive conductor during pressing may vary in the order of several MΩ to several hundred kΩ. desirable.

  However, when the range of resistance change at the time of pressing indicated by the pressure-sensitive conductor is narrow, there is a problem that sensitivity as a pressure sensor is insufficient depending on the pressing force.

  The problem to be solved by the present invention is to provide a pressure sensor with good sensitivity regardless of the strength of the pressing force.

  According to the embodiment of the present invention, the pressure-sensitive conductor connected in series with the source electrode is connected between the source electrode of the organic transistor and the voltage power source. Since the conductive layer is arranged through a space formed by spacers so that they can be electrically connected in accordance with the pressing operation, the amount of variation in the potential difference between the source and the drain in a wide pressure region is increased. In addition, it is possible to secure a movable region of the first pressure-sensitive conductive layer and the second pressure-sensitive conductive layer during the pressing operation. As a result, it is possible to provide a pressure sensor that has good sensitivity to the pressing force regardless of the strength of the pressing force, and has improved on-off recognition sensitivity in which the conduction state and the insulating state are switched according to the pressing operation.

  Hereinafter, a pressure sensor according to an embodiment of the present invention will be described with reference to the drawings. In the present embodiment, an example will be described in which the pressure sensors according to the present invention are arranged in a matrix and applied to a touch panel type input device. In addition, in order to avoid duplication description, the description of the specification regarding 1st Embodiment and 2nd Embodiment and description of drawing are used about a common point.

  1 and 16 are diagrams showing an example of the configuration of the pressure sensor 1 according to the present embodiment of the present invention. In the present embodiment, the pressure sensors 1 shown in FIGS. 1 and 16 are arranged in a matrix along a predetermined operation surface to constitute a touch panel display. In addition, the use of the pressure sensor 1 of this embodiment is not limited to a touch panel display, but can be applied to a fingerprint sensor, a switch, or the like.

As shown in FIG. 1, the pressure sensor 1 of this embodiment includes an organic transistor 10, a pressure-sensitive conductor 20, and a voltage power supply 30. The organic transistor 10 is a transistor using the organic semiconductor layer 15 (see FIG. 16), and includes a gate electrode 11, a source electrode 12, and a drain electrode 13. The voltage power supply 30 applies a predetermined voltage V _DD to the source electrode 12 of the organic transistor 10. The organic transistor 10 outputs a signal corresponding to the current value between the source and the drain when the predetermined voltage V _DD is applied to the external signal processing device 40. Based on the signal acquired from the organic transistor 10, the signal processing device 40 detects the pressing position or the pressing force related to the pressing operation.

  The pressure sensor 1 of this embodiment is basically the same as the pressure sensor 1 described with reference to FIG. 1 in the first embodiment.

  The pressure-sensitive conductor 20 functions as a variable resistance member whose resistance value changes according to the pressure received by pressing. The pressure-sensitive conductor 20 according to the present embodiment includes a pressure-sensitive conductive layer printed using a pressure-sensitive conductive ink in which conductive particles and elastic particles are dispersed in a binder, and conductive particles and elastic particles dispersed in a binder. A pressure-sensitive conductive layer formed by thinly forming the pressure-sensitive conductive material, or a pressure-sensitive conductive layer obtained by slicing a pressure-sensitive conductive sheet in which conductive particles and elastic particles are dispersed in a binder can be used.

  Although it does not specifically limit, The material similar to 1st Embodiment can be used as electroconductive particle.

  FIG. 16 is a cross-sectional view of the pressure sensor 1 of the present embodiment having the circuit shown in FIG. As shown in FIG. 16, the gate electrode 11, the source electrode 12, and the drain electrode 13 constituting the organic transistor 10 are formed on one main surface of the insulating substrate 2 and covered with the gate insulating layer 14. An organic semiconductor layer 15 is formed above (upward in the drawing along the stacking direction, hereinafter the same). A pressure sensitive conductor 20 is formed on the organic semiconductor layer 15 via an insulating layer 17. Further, the upper surface of the pressure-sensitive conductor 20 (the upper surface in the drawing along the stacking direction, hereinafter the same) is covered with a cover member 50. In the pressure sensor 1 shown in FIG. 16, when the upper surface P of the cover member 50 is pressed, the organic transistor 10 outputs a signal corresponding to the pressing force.

  As shown in FIG. 16, the pressure-sensitive conductor 20 of the present embodiment has a first pressure-sensitive conductive layer 21 and a second pressure-sensitive conductive layer 22, and these first pressure-sensitive conductive layer 21 and second pressure-sensitive conductor. A space 23 is formed between the conductive layer 22 and the spacer 60. In the example shown in FIG. 16, one main surface 21 a of the first pressure-sensitive conductive layer 21 and one main surface 22 a of the second pressure-sensitive conductive layer 22 are surfaces to which a pressing force is applied along the arrow F direction in the drawing. Yes, both main surfaces 21a, 22a are arranged in parallel. Moreover, both the main surfaces 21a and 22a are arrange | positioned perpendicularly | vertically with respect to the direction (F direction in a figure) to which a pressing force is applied. Furthermore, the one principal surface 21 a of the first pressure-sensitive conductive layer 21 and the one principal surface 22 a of the second pressure-sensitive conductive layer 22 are disposed so as to face each other through the space 23. In the present embodiment, a spacer 60 is disposed between the insulating layer 17 and the cover member 50, and a space 23 is formed between the first pressure-sensitive conductive layer 21 and the second pressure-sensitive conductive layer 22 by the spacer 60. ing. As shown in the figure, the spacer 60 is arranged in parallel with the one principal surface 21 a of the first pressure-sensitive conductive layer 21 and the one principal surface 22 a of the second pressure-sensitive conductive layer 22.

  The spacer 60 of the present embodiment can be made of an insulating base material such as polyethylene terephthalate. The opening (the plane or bottom surface of the space 23) formed by the spacer 60 can be appropriately set according to the size of the operation switch. The spacer 60 of this example is fixed to the insulating layer 17 and the cover member 50 by adhesive layers 61a and 61b. The thickness of the spacer 60 including the adhesive layers 61a and 61b (the height of the space 23) can be 50 μm to 200 μm, preferably about 75 μm to 150 μm, and more preferably 100 μm or less. The thickness of the spacer 60 in this example is 75 μm or less. In the space 23 formed by the spacer 60 and the adhesive layers 61a and 61b, the first pad electrode 18, the second pad electrode 19, the first pressure-sensitive conductive layer 21, and the second pressure-sensitive conductive layer 22 are formed. The distance between the first pressure-sensitive conductive layer 21 and the second pressure-sensitive conductive layer 22 in this example is about 30 μm. The distance between the first pressure-sensitive conductive layer 21 and the second pressure-sensitive conductive layer 22 is not particularly limited, and the thickness of the insulating layer 17, the thickness of the cover member 50, the first pressure-sensitive conductive layer 21, and the second pressure-sensitive conductive layer. Considering factors such as the thickness of the conductive layer 22, the thickness of the spacer, the pressure resistance characteristics of the pressure-sensitive conductive layers 21 and 22, the magnitude of the pressing force applied during the pressing operation, and the threshold value for on / off identification Can be set as appropriate based on experiments. The space 23 is not limited between the first pressure-sensitive conductive layer 21 and the second pressure-sensitive conductive layer 22 according to the configuration of the pressure-sensitive sensor 1, but the first pressure-sensitive conductive layer 21 and the first pad electrode 18. Or between the second pressure-sensitive conductive layer 22 and the second pad electrode 19.

  When the user performs a pressing operation and the cover member 50 is pressed along the direction of arrow F in FIG. 16, the one principal surface 21 a of the first pressure-sensitive conductive layer 21 and the one principal surface 22 a of the second pressure-sensitive conductive layer 22. Since a pressing force in the direction of arrow F is applied to the second pressure-sensitive conductive layer 22, the second pressure-sensitive conductive layer 22 arranged on the cover member 50 side moves in the space 23 to the insulating layer 17 side. When the second pressure-sensitive conductive layer 22 contacts the first pressure-sensitive conductive layer 21, the first pressure-sensitive conductive layer 21 and the second pressure-sensitive conductive layer 22 are electrically connected in series and are in a conductive state (ON State). On the other hand, when the applied pressing force is released, the second pressure-sensitive conductive layer 22 is separated from the first pressure-sensitive conductive layer 21 and moves in the space 23 toward the cover member 50. Thus, the space 23 formed between the first pressure-sensitive conductive layer 21 and the second pressure-sensitive conductive layer 22 becomes a movable region of the first pressure-sensitive conductive layer 21 and the second pressure-sensitive conductive layer 22. Therefore, the first pressure-sensitive conductive layer 21 can be brought into contact with or separated from the second pressure-sensitive conductive layer 22 in accordance with the pressing operation. In order to bring the first pressure-sensitive conductive layer 21 into contact with the second pressure-sensitive conductive layer 22, it is necessary to apply a pressing force for moving the second pressure-sensitive conductive layer 22 by a distance corresponding to the thickness of the space 23. is there. The first pressure-sensitive conductive layer 21 and the second pressure-sensitive conductive layer can be brought into contact with the second pressure-sensitive conductive layer 22 when a pressing force of a predetermined value or more is applied. The ON state due to the contact of 22 and the OFF state due to the separation between the first pressure-sensitive conductive layer 21 and the second pressure-sensitive conductive layer 22 can be clearly distinguished.

  By forming the space 23 with the spacer 60, the on / off recognition sensitivity according to the pressing operation can be improved as in the first embodiment.

  The pressure sensor 1 of the present embodiment includes a first pad electrode 18 that can contact or contact the first pressure-sensitive conductive layer 21, and a second pad electrode 19 that can contact or contact the second pressure-sensitive conductive layer 22. Further, the first pad electrode 18 is electrically connected to either the source electrode 12 or the voltage power supply 30, and the second pad electrode 19 is electrically connected to either the source electrode 12 or the voltage power supply 30. It can be configured to be connected.

  In the example shown in FIG. 16, the lower surface side of the first pressure-sensitive conductive layer 21 arranged on the lower side of the pressure-sensitive conductor 20 of the present embodiment, that is, the insulating layer 17 and the first pressure-sensitive conductive layer 21. A first pad electrode 18 is formed between them. The first pressure-sensitive conductive layer 21 (pressure-sensitive conductor 20) is electrically connected in series with the source electrode 12 through the first pad electrode 18 and the first pad electrode via 18a connected thereto. Further, as shown in the figure, the upper surface side of the second pressure-sensitive conductive layer 22 disposed on the upper side of the pressure-sensitive conductor 20, that is, between the cover member 50 and the second pressure-sensitive conductive layer 22. A second pad electrode 19 is formed. The second pressure-sensitive conductive layer 22 is electrically connected to the voltage power supply 30 through the second pad electrode 19. The second pad electrode 19 and the first pad electrode 18 connected to the voltage power source 30 can be conducted through the pressure-sensitive conductor 20 (pressure-sensitive conductive layers 21 and 22).

  FIG. 16 shows an example in which the first pressure-sensitive conductive layer 21 is disposed below the second pressure-sensitive conductive layer 22, but the second pressure-sensitive conductive layer 22 is disposed on the lower side, that is, on the insulating layer 17 side. It can also be arranged.

  In the present embodiment, the first pressure-sensitive conductive layer 21 and the second pressure-sensitive conductive layer 22 constituting the pressure-sensitive conductor 20 have different pressure resistance characteristics. The pressure resistance characteristic of the present embodiment is a mode of change in resistance value with respect to an applied pressure value at the time of pressing. The pressure resistance characteristic can be evaluated based on a resistance value in a region of a predetermined applied pressure value, a change amount of the resistance value, and the like.

    The reason why the pressure-sensitive conductive layers 21 and 22 having different pressure resistance characteristics are electrically connected in series is the same as the reason described in the first embodiment.

  Further, the method for adjusting the pressure resistance characteristic of the pressure-sensitive conductive layer 21 (the method for obtaining the pressure-sensitive conductor 20 having an arbitrary pressure resistance characteristic) is the pressure of the pressure-sensitive conductor 20 of the first embodiment and the second embodiment. This is common with the method of adjusting the resistance characteristics.

  In this manner, the pressure-sensitive conductive layer 21 having a high resistance change rate in a region having a relatively low pressure value can be electrically connected to the pressure-sensitive conductive layer 22 having a high resistance change rate in a region having a medium to high pressure value. The pressure-sensitive conductor 20 is configured in such a manner that it is electrically inserted in series between the voltage power source 30 and the source electrode 12 of the organic transistor 10 to cause a large resistance change in a wide pressure region. Therefore, the potential difference between the source and the drain also increases, and as a result, the pressure sensor 1 having high sensitivity in a wide pressure region can be provided.

  Hereinafter, since the manufacturing method of the pressure sensor 1 of this embodiment is common with the method demonstrated based on FIGS. 18-26 in 2nd Embodiment, the description is used and it abbreviate | omits here. .

  27 and 28 are diagrams showing different configuration examples of the pressure sensor 1 of the present embodiment. Since the structure of the pressure sensor 1 of FIG.27 and FIG.28 was demonstrated in 2nd Embodiment, the description is used in this embodiment. Since the connection relationship between the pressure sensor 1 and the voltage power source shown in FIGS. 27 and 28 is the same as that of the pressure sensor 1 of the present embodiment described above, the illustration thereof is omitted in the drawings.

  In addition, the material and manufacturing method for manufacturing the organic transistor 10 are not limited to the above, The material and manufacturing method known at the time of application can be applied suitably.

  In the present specification and drawings, a unit of pressure sensor 1 will be described as an example for convenience of explanation. In the present embodiment, a plurality of pressure sensors 1 shown in FIG. The pressure sensor 1 having a planar shape can be produced by arranging it in a matrix on a parallel plane), and a touch panel display can be configured. By producing the planar pressure sensor 1 in this way, the pressure distribution signal on the operation surface can be detected based on the detection results of the organic transistors 10 similarly arranged in a matrix. Further, by acquiring in advance a current change between the source electrode 12 and the drain electrode 13 with respect to a predetermined pressing force, the magnitude of the pressure when the pressure sensor 1 is pressed can also be detected.

  As described above, according to the pressure sensor 1 in which the organic transistor 10 and the pressure-sensitive conductor 20 according to the present embodiment are combined in the present invention, the pressure-sensitive conductive layers 21 and 22 having different pressure resistance characteristics are arranged to face each other. Since the voltage source 30 and the source electrode 12 are connected in series with the source electrode 12, the amount of variation in the potential difference between the source and drain with respect to a wide range of pressing force can be increased. As a result, it is possible to provide the pressure sensor 1 (touch panel display) with good sensitivity regardless of the strength of the pressing force.

  The embodiment described above is described for facilitating understanding of the present invention, and is not described for limiting the present invention. Therefore, each element disclosed in the above embodiment is intended to include all design changes and equivalents belonging to the technical scope of the present invention.

DESCRIPTION OF SYMBOLS 1 ... Pressure sensor 100 ... Pressure sensor module 2 ... Insulating base material 10 ... Organic transistor 11 ... Gate electrode 12 ... Source electrode 13 ... Drain electrode 14 ... Gate insulating layer 15 ... Organic-semiconductor layers 16, 17 ... Insulating layers 18, 18a ... 1st pad electrode (18 ... electrode, 18a ... via)
18a '... via hole 19 ... second pad electrode 20 ... pressure sensitive conductor 21 ... first pressure sensitive conductive layer 22 ... second pressure sensitive conductive layer 23 ... space, opening 231 ... first space 232 ... second space 30 ... Voltage power supply 40 ... Signal processing device 50 ... Cover member 60 ... Spacer 61a, 61b ... Adhesive layer 62A ... First opening 62B ... Second opening 70 ... Wiring WL ... Word line BL ... Bit line

Claims (20)

An insulating substrate;
An organic transistor provided on one main surface side of the insulating substrate;
A voltage power supply for applying a predetermined voltage to the source electrode of the organic transistor;
A pressure-sensitive conductor disposed substantially parallel to the insulating substrate and connected in series with the source electrode;
On the xy coordinate plane parallel to the main surface of the pressure-sensitive conductor to which pressure is applied according to the pressing operation, the organic transistor and the pressure-sensitive conductor are arranged in parallel at different positions, and according to the pressing operation. A pressure sensor which is electrically connectable.   In the thickness direction of the pressure sensor parallel to the thickness direction of the insulating substrate, the difference between the height position of the installation surface of the pressure-sensitive conductor and the height position of the installation surface of the organic transistor is a predetermined value. The pressure sensor according to claim 1, wherein   2. The pressure sensor according to claim 1, wherein at least a part of the installation surface of the pressure-sensitive conductor and at least a part of the installation surface of the organic transistor are formed on the same xy coordinate plane. .   The pressure sensor according to any one of claims 1 to 3, wherein the electrode to which the pressure-sensitive conductor is connected is a source electrode of the organic transistor. The pressure-sensitive conductor included in the pressure sensor has a first pressure-sensitive conductive layer and a second pressure-sensitive conductive layer having different pressure resistance characteristics,
The first pressure-sensitive conductive layer has a resistance change rate with respect to pressure in the first pressure region higher than a resistance change rate with respect to pressure in the second pressure region other than the first pressure region,
The second pressure-sensitive conductive layer is characterized in that a rate of change of resistance with respect to the pressure in the second pressure region is higher than a rate of change of resistance with respect to the pressure in the second pressure region of the first pressure-sensitive conductive layer. The pressure sensor according to any one of claims 1 to 4. An insulating substrate;
An organic transistor provided on one main surface of the insulating substrate;
A voltage power supply for applying a predetermined voltage to the source electrode of the organic transistor;
A pressure sensor comprising a pressure-sensitive conductor connected in series with the source electrode, or a pressure sensor group comprising a plurality of the pressure sensors;
A word line and a bit line respectively connected to the pressure sensors arranged two-dimensionally in a predetermined region,
The pressure sensor module, wherein the pressure sensor or the pressure sensor group adjacent to each other along either the word line or the bit line has different pressure detection characteristics.   The pressure-sensitive conductors of the pressure sensors adjacent along one of the word lines or the bit lines, or the pressure sensor groups adjacent along either the word line or the bit lines. The pressure sensor module according to claim 6, wherein the pressure-sensitive conductor groups have different pressure resistance characteristics.   Among the pressure-sensitive conductors of the pressure sensors adjacent to each other or the pressure-sensitive conductor groups of the pressure sensor groups adjacent to each other, one of the pressure-sensitive conductors or the pressure-sensitive conductor group is: The rate of resistance change with respect to pressure in the first pressure region is higher than the rate of change in resistance with respect to pressure in the second pressure region other than the first pressure region. The resistance change rate with respect to the pressure in the two pressure regions is higher than the resistance change rate with respect to the pressure in the second pressure region of the one pressure-sensitive conductor or the pressure-sensitive conductor group. 8. The pressure sensor module according to 7.   The pressure-sensitive conductors of the pressure sensors adjacent to each other along either the word line or the bit line are formed using different pressure-sensitive conductive inks. The pressure sensor module according to claim 8.   The pressure-sensitive conductor groups of the pressure sensor groups adjacent to each other along either the word line or the bit line are different pressure-sensitive conductive inks or different combinations of pressure-sensitive conductive inks. It forms using, The pressure sensor module as described in any one of Claims 6-8 characterized by the above-mentioned.   The pressure sensor module according to any one of claims 6 to 10, wherein the pressure-sensitive conductor included in the pressure sensor includes a plurality of pressure-sensitive conductive layers having different pressure resistance characteristics. The pressure-sensitive conductor includes a first pressure-sensitive conductive layer and a second pressure-sensitive conductive layer,
The first pressure-sensitive conductive layer has a resistance change rate with respect to pressure in a third pressure region higher than a resistance change rate with respect to pressure in a fourth pressure region other than the third pressure region,
The second pressure-sensitive conductive layer is characterized in that a rate of change of resistance with respect to the pressure in the fourth pressure region is higher than a rate of change of resistance with respect to the pressure in the fourth pressure region of the first pressure-sensitive conductive layer. The pressure sensor module according to claim 11. An insulating substrate;
An organic transistor provided on one main surface of the insulating substrate;
A voltage power supply for applying a predetermined voltage to the source electrode of the organic transistor;
A pressure-sensitive conductor disposed between the voltage power source and the source electrode and connected in series with the source electrode;
The pressure-sensitive conductor has a first pressure-sensitive conductive layer and a second pressure-sensitive conductive layer having different pressure resistance characteristics,
The pressure sensor further comprising a spacer that forms a space between the first pressure-sensitive conductive layer and the second pressure-sensitive conductive layer. The first pressure-sensitive conductive layer has a resistance change rate with respect to pressure in the first pressure region higher than a resistance change rate with respect to pressure in the second pressure region other than the first pressure region,
The second pressure-sensitive conductive layer is characterized in that a rate of change of resistance with respect to the pressure in the second pressure region is higher than a rate of change of resistance with respect to the pressure in the second pressure region of the first pressure-sensitive conductive layer. The pressure sensor according to claim 13.   In the first pressure-sensitive conductive layer and the second pressure-sensitive conductive layer, the main surface of the first pressure-sensitive conductive layer to which pressure is applied and the main surface of the second pressure-sensitive conductive layer are parallel to each other. The pressure sensor according to claim 13, wherein the pressure sensor is electrically connected in series according to a pressing operation.   In the first pressure-sensitive conductive layer and the second pressure-sensitive conductive layer, one main surface of the first pressure-sensitive conductive layer to which pressure is applied and one main surface of the second pressure-sensitive conductive layer face each other. The pressure sensor according to claim 13, wherein the pressure sensor is electrically connected in series according to a pressing operation.   The first pressure-sensitive conductive layer and the second pressure-sensitive conductive layer are on the xy coordinates along the main surface of the first pressure-sensitive conductive layer and the main surface of the second pressure-sensitive conductive layer to which pressure is applied. The pressure sensor according to any one of claims 13 to 15, wherein the pressure sensor is arranged in parallel at different positions and can be electrically connected in series according to a pressing operation. A first pad electrode in contact with or contactable with the first pressure sensitive conductive layer;
A second pad electrode in contact with or contactable with the second pressure-sensitive conductive layer,
The first pad electrode is electrically connected to either the source electrode or the voltage power source,
The pressure sensor according to any one of claims 13 to 17, wherein the second pad electrode is electrically connected to either the source electrode or the voltage power source.   The space is provided between the first pressure-sensitive conductive layer and the first pad electrode, or between the second pressure-sensitive conductive layer and the second pad electrode, and further includes a spacer that forms the space. The pressure sensor according to claim 18 provided.   The first pressure-sensitive conductive layer and the second pressure-sensitive conductive layer are printed patterns formed by printing using a pressure-sensitive conductive ink containing a conductive material. The pressure sensor according to any one of 19.

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