JP3908266B2 - Semiconductor pressure sensor and manufacturing method thereof - Google Patents

Description

  The present invention relates to a semiconductor pressure sensor used for measuring atmospheric pressure or gas pressure, and a method for manufacturing the same, and particularly to miniaturization by connection via a bump and to the bump due to a difference in thermal expansion of an object to be connected. The present invention relates to a semiconductor pressure sensor that mitigates the influence of working stress and improves the reliability of the connection and the sensor, and a manufacturing method thereof.

  A pressure-sensitive chip for a semiconductor pressure sensor is made of a silicon single crystal similar to an integrated circuit (IC) component, and includes a diaphragm formed by reducing its thickness at the center of the chip. A piezoresistive pressure sensitive gauge (semiconductor strain gauge) is formed on the surface of the diaphragm. When pressure is applied to the diaphragm, the diaphragm is deformed to change the electric resistance of the pressure sensitive gauge, and the change in the electric resistance is detected as an electric signal, whereby the pressure or the change in pressure is measured. Semiconductor pressure sensors include a relative pressure type semiconductor pressure sensor that measures relative pressure and an absolute pressure type semiconductor pressure sensor that measures absolute pressure.

  A sectional view of the absolute pressure type semiconductor pressure sensor is shown in FIG. A vacuum space is formed between the diaphragm 20 and the glass substrate 23 by bonding the glass substrate 23 to the back side of the pressure sensitive chip 21. The pressure applied to the surface of the diaphragm 20 is measured as an absolute pressure based on the vacuum pressure on the back side. The figure shows a state in which the diaphragm 20 is curved by the pressure applied to the surface of the pressure sensitive chip 21.

  As a conventional absolute pressure type semiconductor pressure sensor, a sensor in which a pressure sensitive chip 21 is protected by a casing has been proposed (for example, see Patent Document 1). An example of this pressure sensor is shown in FIG. A glass substrate 23 is attached to a pressure-sensitive chip 21 in which a piezoresistive pressure-sensitive gauge (not shown) is formed on a silicon substrate, and a vacuum chamber 24 is formed therebetween. The pressure-sensitive chip 21 and the glass substrate 23 are covered with a casing 25, and the pressure-sensitive chip 21 is connected to the leads 27 through bonding wires 26.

  In such an absolute pressure type semiconductor pressure sensor, the presence of the housing 25 prevents damage to the bonding wire 26 and deterioration of the pressure sensitive gauge electrode. Connecting the pressure-sensitive gauge electrode and the external measurement electronic device directly with solder generates stress due to a difference in thermal expansion and causes fluctuations in the sensor output. Is used. As a result, it is difficult to further reduce the size of the structure having the housing 25, the bonding wire 26 and the lead 27.

  In order to reduce the size of the absolute pressure type semiconductor pressure sensor, one in which a pressure sensitive chip and a lead are electrically connected by a conductive bump has been proposed (for example, see Patent Document 2). An example of this pressure sensor is shown in FIG. A bump 33 having conductivity is formed on one surface 32 of the pressure-sensitive chip 31, and the bump 33 and the lead 36 are electrically connected in a state where the one surface 32 of the pressure-sensitive chip 31 and the one surface 35 of the base body 34 are opposed to each other. Connected to.

  However, in this structure, since the pressure-sensitive chip 31 and the lead 36 are firmly connected via the bumps 33, if a temperature change occurs, the difference in thermal expansion between the pressure-sensitive chip 31 and the measurement electronic device. Is generated, and the stress tends to concentrate on the bumps 33. If the distortion of the bumps 33 increases due to this stress concentration, problems such as electrode peeling and increased resistance may occur. Further, as a result of the fluctuation in the resistance value of the piezoresistive pressure-sensitive gauge due to this stress, the sensor mistakes that the fluctuation in pressure has occurred. Therefore, when a reduction in size is achieved by connection using the bumps 33, it is necessary to provide some stress relaxation function to the bumps 33.

On the other hand, in recent years, with the miniaturization of semiconductor devices, miniaturization of semiconductor packages has been attempted. Among them, a resin post structure is provided in the solder bump portion, and the stress that concentrates on the solder bump is eased by this resin post, thereby improving the reliability of the connection portion and reducing the size. (For example, see Patent Document 3). An example of this semiconductor package is shown in FIG. The resin protrusion 44 provided on the insulating layer 43 of the wafer 41 is covered with a conductive layer 45, and is connected by forming a post 46 configured to disperse and absorb stress by deformation of the resin protrusion 44. The reliability of the semiconductor package is improved, and the semiconductor package is downsized.
JP 2000-88687 A JP 2002-82009 A JP 2002-280476 A

  The present invention has been made in view of the above circumstances, and by connecting a pressure-sensitive chip and a measurement electronic device using a bump having a stress relaxation function, the pressure measurement accuracy and the reliability of connection can be reduced. An object of the present invention is to provide a semiconductor pressure sensor and a method for manufacturing the same.

In order to achieve this object, a first invention according to the present invention includes a pressure-sensitive gauge disposed in a region of the diaphragm, a pressure-sensitive gauge electrode disposed in a region other than the diaphragm, the pressure-sensitive gauge, and the A pressure-sensitive chip having a pressure-sensitive lead for electrically connecting the pressure-sensitive gauge electrode; a first opening disposed on the pressure-sensitive chip and exposing the diaphragm; and a part of the pressure-sensitive gauge electrode An insulating resin layer having a second opening to be exposed; a conductive layer disposed on the insulating resin layer and electrically connected to the pressure-sensitive gauge electrode through the second opening; and the conductive layer It is characterized by having at least a bump arranged on the top .

According to a second aspect of the present invention, in the first aspect, the insulating resin layer is made of a photosensitive resin .

According to a third aspect of the present invention, a pressure sensitive gauge disposed in a region of the diaphragm, a pressure sensitive gauge electrode disposed in a region other than the diaphragm, and the pressure sensitive gauge and the pressure sensitive gauge electrode are electrically connected. A pressure-sensitive chip having a pressure-sensitive lead to be connected, a first opening disposed on the pressure-sensitive chip and exposing the diaphragm, and a second opening exposing a part of the pressure-sensitive gauge electrode; An insulating resin layer, a conductive layer disposed on the insulating resin layer, electrically connected to the pressure-sensitive gauge electrode through the second opening, and a bump disposed on the conductive layer A method of manufacturing a semiconductor pressure sensor comprising at least an insulating resin layer made of a photosensitive resin on the pressure-sensitive chip so as to cover the pressure-sensitive gauge, the pressure-sensitive gauge electrode, and the pressure-sensitive lead. Step A, the insulating tree Forming a first opening for exposing the diaphragm and a second opening for exposing a part of the pressure-sensitive gauge electrode in the layer; electrically passing through the second opening and the pressure-sensitive gauge electrode; It is characterized by comprising at least a step C of forming a conductive layer so as to be connected .

According to a fourth aspect of the present invention, in the third aspect, the step B forms the first opening and the second opening at the same time .

As shown in FIG. 1 , the semiconductor pressure sensor according to the first aspect of the present invention includes a pressure-sensitive gauge G disposed in a region of the diaphragm 2, a pressure-sensitive gauge electrode 5 disposed in a region other than the diaphragm 2, and the above-described sensitivity. A pressure-sensitive chip 1 having a pressure gauge and a pressure-sensitive lead L that electrically connects the pressure-sensitive gauge electrode is provided, and an insulating resin layer 10 is disposed on the pressure-sensitive chip 1. This insulating resin layer 10 has a first opening for exposing the diaphragm 2 as shown in FIG. 5 and a second opening for exposing a part of the pressure sensitive gauge electrode 5 as shown in FIG. Provided. On the insulating resin layer 10, a conductive layer 8 that is electrically connected to the pressure-sensitive gauge electrode 5 through the second opening as shown in FIG. 9 is disposed. Has a configuration in which bumps 9 are arranged.
According to this configuration, since the insulating resin layer 10 is almost entirely below the bumps 9, the bumps 9 are less susceptible to the stress caused by the connection between the pressure sensitive chip 1 and the measuring electronic device. As a result, the connection state of the bump to the measurement electronic device can be stably maintained, and inconveniences such as an increase in resistance due to a change in the connection state, electrode peeling, and extreme deformation of the bump can be reliably prevented.

In the semiconductor pressure sensor according to the first aspect of the present invention, the connection position between the conductive layer electrically connected to the pressure sensitive gauge electrode and the bump is a position where the resistance value of the piezoresistive pressure sensitive gauge is less likely to be affected. By doing so, it is possible to eliminate the influence of the stress caused by the connection via the bumps on the diaphragm that is susceptible to the influence of the stress, so that the measurement accuracy of the semiconductor pressure sensor is improved. Furthermore, measures such as newly providing a buffer member for absorbing the stress generated by the connection with the measuring electronic device are not required. As a result, an increase in the thickness of the pressure sensor due to the connection between the pressure-sensitive chip and the measurement electronic device is suppressed, and the semiconductor pressure sensor can be reduced in size and cost can be reduced.

According to the method for manufacturing a semiconductor pressure sensor according to the present invention ( third invention ), the connection position between the conductive layer and the bump is formed at a position where the resistance value of the piezoresistive pressure sensitive gauge is unlikely to be affected. Therefore, as described above, it is possible to obtain a semiconductor pressure sensor that can eliminate the influence of the stress caused by the connection via the bump on the diaphragm that is easily affected by the stress. At that time, by using an insulating resin layer made of a photosensitive resin, a first opening for exposing the diaphragm 2 as shown in FIG. 5 and a part of the pressure-sensitive gauge electrode 5 as shown in FIG. It is possible to easily form the second opening that exposes. In particular, since the two openings can be formed at the same time, it is possible to shorten the formation time and reduce the cost by reducing the number of steps for forming the two openings . As a result, the manufacturing efficiency of the semiconductor pressure sensor can be improved and the cost can be reduced .

  Embodiments of a semiconductor pressure sensor according to the present invention will be specifically described below with reference to the accompanying drawings.

  1 is an upper perspective view showing an example of the structure of a semiconductor pressure sensor according to the present invention, FIG. 2 is a cross-sectional view of an absolute pressure type semiconductor pressure sensor according to the present invention, and FIG. 3 is a diagram of the semiconductor pressure sensor shown in FIG. It is an enlarged view (cross-sectional view along the AA line in FIG. 1) of a pressure-sensitive gauge electrode part.

  In these figures, 1 is a pressure sensitive chip. The pressure-sensitive chip 1 is made of a silicon single crystal having a thickness of about 200 to 300 μm, and the central portion of the pressure-sensitive chip 1 is thinned to about 20 to 50 μm by etching or the like applied from the back surface. Further, this thin portion has, for example, a circular shape in plan view. Four piezoresistive pressure-sensitive gauges G and piezoresistive pressure-sensitive leads L (see FIG. 1) are diffused and formed on the surface of the thin portion. A pressure-sensitive gauge electrode 5 is formed on the outer periphery of the pressure-sensitive chip 1. The pressure-sensitive gauge electrode 5 and the piezoresistive pressure-sensitive gauge G are connected to the pressure-sensitive chip from the end of each piezoresistive pressure-sensitive gauge G. 1 is connected by a piezoresistive pressure-sensitive lead L extending to the outer peripheral portion of 1. Thereby, a Wheatstone bridge circuit is formed. A concave portion 4 is formed on the back surface side of the pressure-sensitive chip 1 by thinning the central portion of the pressure-sensitive chip 1. By joining, a pressure sensor is obtained in which the reference pressure is in the space (first space) S sandwiched between the recess 4 and the glass substrate 3 and maintained in a vacuum. Further, when an external force is applied to the thin portion (diaphragm 2) of the pressure-sensitive chip 1, the diaphragm 2 is deformed, and the individual gauge resistance formed on the surface of the diaphragm 2 changes. This change in resistance in the Wheatstone bridge circuit is used to monitor fluctuations in sensor output and convert to pressure.

  The surface of the pressure-sensitive chip 1 is covered with an insulating resin layer 10 having an open portion on the pressure-sensitive gauge electrode 5 and the diaphragm 2, and a resin protrusion 6 is formed on a part of the pressure-sensitive gauge electrode 5. Has been. The resin protrusion 6 is partially or entirely covered with a seed layer 7 and a conductive layer 8 to form a post P, and a bump 9 is formed so as to cover the post P. The bump 9 is connected to the pressure sensitive gauge electrode 5 through the seed layer 7 and the conductive layer 8 so as to be electrically conductive. As a result, when the bump 9 is connected to a measuring electronic device (not shown), the bump 9 is The measurement electronic device and the pressure sensitive gauge electrode 5 are connected so as to be electrically conductive. As the pressure-sensitive gauge electrode 5, various conductive materials can be used, but here, aluminum is used. Various forms can be employed for the number, shape, and mounting position of the piezoresistive pressure-sensitive gauge G, the pressure-sensitive gauge electrode 5, and the piezoresistive pressure-sensitive lead L, and there are no particular limitations.

The resin protrusion 6 protrudes from the pressure-sensitive gauge electrode 5 and has a semicircular shape with a trapezoidal cross section or a flat portion at the top.
The resin protrusion 6 is made of, for example, polyimide, epoxy resin, silicone resin or the like, and has a thickness of, for example, 25 to 100 μm, and can be formed by a spin coating method, a printing method, a laminating method, or the like. is there.

  In consideration of the stress acting on the resin protrusion 6 when used as a pressure sensor, it is desirable that the resin constituting the resin protrusion 6 has a Young's modulus (elastic modulus) of 5 GPa or less. In addition, the individual resin protrusions 6 surrounding the diaphragm 2 are symmetrical with respect to the diaphragm 2 when viewed in plan in order to prevent variations in stress acting on the resin protrusions 6 when used as pressure sensors. It is desirable to be arranged at the position.

  The film-like seed layer 7 covered with the resin protrusion 6 is also formed on the pressure sensitive gauge electrode 5 exposed around the resin protrusion 6 as shown in FIG. The gauge electrode 5 is connected to be electrically conductive. A film-like conductive layer 8 is formed on the seed layer 7 so as to cover it.

  The seed layer 7 functions as a power supply layer or UBM (under bump metal) in the electrolytic plating (hereinafter referred to as “plating”) process of the conductive layer 8. The function as the UBM is a function such as a barrier for securing adhesion between the conductive layer 8 and the resin protrusion 6 and preventing metal diffusion between the pressure sensitive gauge electrode 5 and the conductive layer 8. It is. As the seed layer 7, for example, a metal or an alloy such as Cr, Cu, Ni, Ti, W, Ta, Mg, or Au can be used, but the seed layer 7 is not limited to a configuration including a single metal layer, and a plurality of metal layers It is also possible to adopt a configuration in which layers are stacked. In the present embodiment, the Cr layer having a thickness of about 40 nm covering the surface of the pressure-sensitive gauge electrode 5 and the resin protrusion 6 exposed around the bottom of the resin protrusion 6, and the thickness covering this Cr layer. A two-layer structure in which a Cu layer of about 100 to 150 nm is formed in a laminated state by a sputtering method is adopted.

  As the conductive layer 8, a plating layer obtained by plating a metal or alloy such as Cu or Ni is employed. However, the conductive layer 8 is not limited to a configuration including only one metal layer (including an alloy layer; the same applies hereinafter), and for example, a configuration in which a plurality of metal layers are stacked can be employed. In the present embodiment, a copper plating layer having a thickness of about 3 to 20 μm covering the seed layer 7, a Ni plating layer having a thickness of about 1 to 10 μm covering the copper plating layer, and a thickness covering the Ni plating layer. A three-layer structure composed of an Au plating layer of about 0.1 to 1.0 μm is adopted.

  As shown in FIG. 4, the absolute pressure type semiconductor pressure sensor is mounted on a measurement electronic device (circuit board 12) via bumps 9. In addition, a space (second space) 13 sandwiched between the surface of the diaphragm 2 and the circuit board 12 is a space (not shown) that is an object of pressure measurement through a hole H formed in the circuit board 12. The space 13 is shielded by sealing the periphery of the pressure sensitive chip 1 with a filler 14. Then, the pressure applied to the surface of the diaphragm 2 through the hole H and the space 13 is measured as an absolute pressure based on the vacuum pressure in the space S.

  According to this absolute pressure type semiconductor pressure sensor, since the bump 9 is formed so as to cover the resin protrusion 6, the stress caused by the difference in thermal expansion between the pressure sensitive chip 1 and the measuring electronic device is made of resin. It can be absorbed by the deformation of the protrusion 6. As a result, the connection state between the bump 9 and the measurement electronic device can be stably maintained, and inconveniences such as electrode peeling can be reliably prevented. Furthermore, the influence of stress on the sensor can also be suppressed. Further, since a sufficient contact area between the bump 9 and the resin protrusion 6 is ensured, the stress acting on the bump 9 can be reliably transmitted to the resin protrusion 6, and the resin can be transferred from the bump 9 to the resin. The fixing force transmitted to the pressure-sensitive chip 1 side through the protrusion 6 is improved, and peeling of the bumps 9 due to the action of stress can be prevented.

  Next, an example of a manufacturing method of the absolute pressure type semiconductor pressure sensor described above will be described. 5 to 9 are process diagrams showing a manufacturing method of the absolute pressure type semiconductor pressure sensor shown in FIG. In this manufacturing method, the pressure-sensitive chip 1 is usually formed in a wafer shape, but here, individual chips will be described.

  First, the pressure sensitive chip 1 in which the diaphragm 2 is formed, the piezoresistive pressure sensitive gauge G and the piezoresistive pressure sensitive lead L are diffused and formed on the surface, and the pressure sensitive gauge electrode 5 is formed around the diaphragm 2 is formed. An insulating resin layer 10 is formed on the pressure sensitive chip 1. The insulating resin layer 10 is formed so as to cover the piezoresistive pressure-sensitive gauge G and the pressure-sensitive gauge electrode 5 with a thickness of about 5 to 10 μm by spin-coating a liquid photosensitive resin such as photosensitive polyimide. .

Next, as shown in FIG. 5, a part of the insulating resin layer 10 located on the pressure sensitive gauge electrode 5 is removed by photolithography, and an opening that forms a ring shape in plan view on the pressure sensitive gauge electrode 5 is formed. The second portion (second opening) is formed. As a result, an insulating resin layer 10 having an opening (second opening) is formed on the pressure-sensitive gauge electrode 5, and a resin protrusion 6 is formed in the opening . At the same time, unnecessary insulating resin layer 10 on the diaphragm is removed. Thereby, the opening part (1st opening part) which exposes the diaphragm 2 is obtained. In this case, the edge of the pressure-sensitive gauge electrode 5 is covered with the insulating resin layer 10, and the insulating resin layer 10 is removed so that the pressure-sensitive gauge electrode 5 is exposed around the resin protrusion 6, and the diaphragm 2 is removed. The insulating resin layer 10 is removed so that the individual resin protrusions 6 that are surrounded are arranged at positions that are symmetrical about the diaphragm 2 when viewed in plan.

  The planar shape of the opening is not necessarily limited to a ring shape. For example, a part of the resin protrusion 6 surrounded by the opening part may be connected to the surrounding insulating resin layer 10 to form an opening part in which the planar shape is C-shaped.

  In this method, since the insulating resin layer 10 and the resin protrusion 6 can be formed at the same time, the formation time and the number of steps can be reduced. Further, in this step, the resin protrusion 6 can be formed in a desired shape and size corresponding to the shape of the bump 9 formed in the subsequent step, and individually corresponding to the shape of the diaphragm 2. The resin protrusion 6 can be formed at a desired position.

  The insulating resin layer 10 can also be formed by attaching a sheet or film formed from a photosensitive resin such as photosensitive polyimide. Also in this case, the insulating resin layer 10 and the resin protrusion 6 are formed by removing a part of the insulating resin layer 10 located on the pressure-sensitive gauge electrode 5 in a ring shape by a photolithography technique to form an open portion. Can be simultaneously formed in a short time.

  Next, after the insulating resin layer 10 and the resin protrusion 6 are formed, the seed layer 7 is formed. Specifically, in the opening of the insulating resin layer 10, the pressure-sensitive gauge electrode 5 exposed around the resin protrusion 6 and the surface of the resin protrusion 6 are formed on the surface of the resin protrusion 6 with a thickness of about 40 nm by sputtering. After forming the layer, a Cu layer having a thickness of about 100 to 500 nm covering the Cr layer is formed by sputtering. As shown in FIG. 6, the seed layer 7 covers the insulating resin layer 10, the resin protrusion 6 and the opening, and is formed over the entire pressure-sensitive chip surface.

  The Cr layer is excellent in adhesion to the pressure sensitive gauge electrode 5, the resin protrusion 6 and the insulating resin layer 10. On the other hand, the Cu layer functions as a power feeding layer in the plating process of the conductive layer 8 to be described later, and also has excellent adhesion to the conductive layer 8, so that the seed layer 7 and the conductive layer 8 are in close contact with each other. Fulfills the function of

  Each metal layer (the aforementioned Cr layer or Cu layer) constituting the seed layer 7 can be formed not only by sputtering but also by vapor deposition. It is also possible to cover the resin protrusion 6 directly with a metal layer (here, Cr layer) by electroless plating.

  After the seed layer 7 is formed, the conductive layer 8 is formed so as to cover the seed layer 7 by plating. In the step of plating the conductive layer 8, first, as shown in FIG. 6, on the pressure-sensitive chip 1 on which the insulating resin layer 10 and the resin protrusion 6 are formed, a region for forming the conductive layer 8 (here, A region where the conductive layer 8 is not formed is formed by forming the resist 11 so as to have an opening in a portion corresponding to the open portion on the pressure-sensitive gauge electrode 5 and the resin protrusion 6 inside thereof. Cover and expose only the region where the conductive layer 8 is to be formed. In forming the resist 11, for example, a liquid photosensitive resin for resist is spin coated to form a resin layer on the pressure sensitive chip 1 on which the insulating resin layer 10 and the resin protrusion 6 are formed. A portion of the resin layer corresponding to the region where the conductive layer 8 is to be formed is removed by photolithography.

  After forming the resist 11, as shown in FIG. 7, the conductive layer 8 is formed on the open portion of the resist 11 by plating. Specifically, after forming a copper plating with a thickness of about 3 to 20 μm covering the seed layer 7, a Ni plating layer with a thickness of about 1 to 10 μm covering the copper plating layer is formed, and further this Ni plating layer A conductive layer 8 having a three-layer structure is formed by forming an Au plating layer having a thickness of about 0.1 to 1.0 μm covering the substrate.

  Note that the formation of the resist 11 having an opening corresponding to the formation region of the conductive layer 8 is not limited to the removal of the photosensitive resin layer by a photolithography technique. For example, a dry film resist is laminated on a pressure-sensitive chip, and a portion of the resist corresponding to the formation region of the conductive layer 8 is removed by laser processing, plasma etching, wet etching, etc. It is also possible to adopt a method for forming an open portion for use.

  When the formation of the conductive layer 8 is completed, the resist 11 is removed, and unnecessary seed layers 7 (such as the seed layer 7 on the insulating resin layer 10 and the diaphragm 2) are removed by etching or the like. Thereafter, bumps 9 made of, for example, solder are formed on the surface of the conductive layer 8. As a method of forming the bump 9. Examples thereof include a printing method, a metal jet method, and a method of placing solder balls on a flux. The bump 9 seals the opening of the insulating resin layer 10 on the pressure sensitive gauge electrode 5.

  Thus, an absolute pressure type semiconductor pressure sensor with bumps 9 having a stress relaxation function as shown in FIG. 3 is formed.

  In addition, this invention is not limited to the following embodiment, A various change is possible. For example, the present invention can be applied to a relative pressure type semiconductor pressure sensor.

  FIG. 8 shows a state in which the relative pressure type semiconductor pressure sensor according to the present invention is mounted on the measurement electronic device (circuit board 12) via the bumps 9. In this relative pressure type semiconductor pressure sensor, a space S sandwiched between the concave portion 4 of the pressure sensitive chip 1 and the glass substrate 3 is a space for pressure measurement via a hole H2 formed in the glass substrate 3 (see FIG. (Not shown). The circuit board 12 has a hole H communicating with the atmosphere. As a result, the air pressure in the space 13 sandwiched between the surface of the diaphragm 2 and the circuit board 12 is atmospheric pressure. Then, the pressure applied to the back surface of the diaphragm 2 through the hole H2 and the space S is measured as a relative pressure based on the atmospheric pressure (atmospheric pressure) of the space 13. The other configuration forming the pressure sensor, the manufacturing method thereof, and the operation and effect are the same as those of the embodiment shown in FIGS.

FIG. 9 is a sectional view showing an example of the structure of another absolute pressure type semiconductor pressure sensor according to the present invention. In this example, a part of the resin protrusion 6 surrounded by the opening (second opening) is connected to the surrounding insulating resin layer 10, and the end of the resin protrusion 6 (pressure-sensitive) Bumps 9 are formed on the conductive layer 8 extending to the upper part of the resin layer 10 located on the side of the gauge electrode 5. In this case, since the resin layer 10 is almost entirely below the bumps 9, the bumps 9 are less susceptible to the stress caused by the connection between the pressure-sensitive chip 1 and the measurement electronic device. In addition, the connection position between the conductive layer 8 and the bump 9 can be set to a position where the resistance value of the piezoresistive pressure sensitive gauge is hardly affected (for example, a position as far as possible from the piezoresistive gauge).

It is an upper perspective view which shows the example of the structure of the semiconductor pressure sensor which concerns on this invention. It is sectional drawing which shows the example of the structure of the absolute pressure type | mold semiconductor pressure sensor which concerns on this invention. It is an enlarged view which shows the cross section of the pressure sensitive gauge electrode part of FIG. It is sectional drawing which shows the condition which mounted the semiconductor pressure sensor of FIG. 2 in the electronic device for a measurement via bump. It is a figure which shows the process of the manufacturing method of the semiconductor pressure sensor of FIG. 2, Comprising: The state which provided the opening part in the insulating resin layer is shown. It is a figure which shows the process of the manufacturing method of the semiconductor pressure sensor of FIG. 2, Comprising: After coat | covering a resist, the state which opened the conductive layer formation part is shown. It is a figure which shows the process of the manufacturing method of the semiconductor pressure sensor of FIG. 2, Comprising: It is an enlarged view which shows the state in which the conductive layer was formed. It is sectional drawing which shows the condition which mounted the relative pressure type | mold semiconductor pressure sensor which concerns on this invention in the electronic device for a measurement via bump. It is sectional drawing which shows the example of the structure of the absolute pressure type | mold semiconductor pressure sensor which concerns on this invention. It is sectional drawing which shows the example of the pressure sensitive chip in the conventional absolute pressure type semiconductor pressure sensor. It is sectional drawing which shows the example of the conventional absolute pressure type | mold semiconductor pressure sensor. It is sectional drawing which shows the example of the conventional semiconductor pressure sensor which has the bump for a connection. It is sectional drawing which shows the example of the conventional semiconductor package which has bump with a resin post.

Claims (4)

A pressure-sensitive gauge disposed in a diaphragm area; a pressure-sensitive gauge electrode disposed in an area other than the diaphragm; and a pressure-sensitive lead electrically connecting the pressure-sensitive gauge and the pressure-sensitive gauge electrode. Pressure-sensitive chip,
An insulating resin layer provided on the pressure-sensitive chip and having a first opening for exposing the diaphragm and a second opening for exposing a part of the pressure-sensitive gauge electrode;
A conductive layer disposed on the insulating resin layer and electrically connected to the pressure-sensitive gauge electrode through the second opening; and
A bump disposed on the conductive layer;
A semiconductor pressure sensor. The semiconductor pressure sensor according to claim 1, wherein the insulating resin layer is made of a photosensitive resin. A pressure-sensitive gauge disposed in a diaphragm area; a pressure-sensitive gauge electrode disposed in an area other than the diaphragm; and a pressure-sensitive lead electrically connecting the pressure-sensitive gauge and the pressure-sensitive gauge electrode. A pressure-sensitive chip, an insulating resin layer provided on the pressure-sensitive chip and having a first opening for exposing the diaphragm and a second opening for exposing a part of the pressure-sensitive gauge electrode, the insulating resin A semiconductor pressure sensor comprising at least a conductive layer disposed on a layer and electrically connected to the pressure-sensitive gauge electrode through the second opening, and a bump disposed on the conductive layer A method,
Forming an insulating resin layer made of a photosensitive resin on the pressure-sensitive chip so as to cover the pressure-sensitive gauge, the pressure-sensitive gauge electrode, and the pressure-sensitive lead;
Forming a first opening for exposing the diaphragm and a second opening for exposing a part of the pressure-sensitive gauge electrode in the insulating resin layer;
Forming a conductive layer so as to be electrically connected to the pressure-sensitive gauge electrode through the second opening,
At least in order. A method for manufacturing a semiconductor pressure sensor. The said process B forms said 1st opening part and said 2nd opening part simultaneously, The manufacturing method of the semiconductor pressure sensor of Claim 3 characterized by the above-mentioned.

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