JP2010056414A - Method of forming wiring, method of manufacturing semiconductor device, semiconductor device, and wiring forming device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To make semiconductor chips conduct each other. <P>SOLUTION: In a method of forming wiring, conductive ink drops R are discharged to a semiconductor substrate 12 from an inkjet head 70 to form the wiring by a conductive layer 16. The method includes a process to form a first conductive layer from the surface 12a to the side 12b of the semiconductor substrate 12, and a process to form a second conductive layer on the backside 12c of the semiconductor substrate 12 and connect the first conductive layer to the second conductive layer. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a wiring forming method, a semiconductor device manufacturing method, a semiconductor device, and a wiring forming apparatus.

  In recent years, in response to demands for miniaturization and high integration of electronic components, development of methods for three-dimensional mounting of semiconductor chips has progressed. As such a method, for example, a method by wire bonding in which electrodes of a plurality of stacked semiconductor chips are electrically connected by wires is known. However, in this method, the outer shape of the semiconductor chip, the position of the electrodes, and the like are limited due to restrictions on the length of the wire itself. Moreover, it becomes necessary to secure a space mainly in the height direction as a region where the wire is routed.

Therefore, instead of wire bonding, a method has been proposed in which conductive ink droplets are ejected from the surface to the side surface of each semiconductor chip from an inkjet head to form a conductive layer between the electrodes (for example, see Patent Document 1). . Specifically, in the technique of Patent Document 1, a groove is formed on the surface of the semiconductor substrate, a conductive layer is then formed on the inner wall surface of the groove, the semiconductor substrate is polished from the back surface, and the semiconductor substrate is divided. The conductive layers of each semiconductor substrate are electrically connected (connected) on the side surfaces (paragraphs 0063 to 0085, 0096 to 0100). As a result, a plurality of semiconductor chips can be stacked, and the above-described restrictions due to wires can be removed.
Japanese Patent No. 4081666

  However, in the technique of Patent Document 1, since the conductive layers of the respective semiconductor substrates are merely connected to each other at the side surfaces, in a semiconductor device that is a stacked body of a plurality of semiconductor chips, the electrodes of one semiconductor chip and the other The semiconductor chips are not electrically connected to each other, and the semiconductor chips cannot substantially be electrically connected to each other.

  Accordingly, a main object of the present invention is to provide a wiring forming method, a semiconductor device manufacturing method, a semiconductor device, and a wiring forming apparatus capable of electrically connecting semiconductor chips in a semiconductor device in which a plurality of semiconductor chips are stacked. It is in.

According to one aspect of the invention,
A wiring formation method for forming a wiring by a conductive layer by discharging conductive ink droplets from an inkjet head to a semiconductor substrate,
Forming a first conductive layer from one side to the side of the front and back sides of the semiconductor substrate;
Forming a second conductive layer on the other surface of the semiconductor substrate and joining the first conductive layer and the second conductive layer;
A method of forming a wiring is provided.

According to another aspect of the invention,
A wiring formation method for forming a wiring by a conductive layer by discharging conductive ink droplets from an inkjet head to a semiconductor substrate,
Forming a first conductive layer from one of the front and back surfaces of the semiconductor substrate to the middle of the side surface;
Forming a second conductive layer from the other surface of the semiconductor substrate to the middle portion of the side surface, and joining the first conductive layer and the second conductive layer;
A method of forming a wiring is provided.

According to another aspect of the invention,
Producing a plurality of semiconductor chips;
Applying an insulation treatment to each of the semiconductor chips;
Laminating and stacking the semiconductor chips together;
With
In the process of manufacturing each semiconductor chip, a first conductive layer is formed from one surface to the side surface of the semiconductor substrate by discharging conductive ink droplets from the inkjet head to the semiconductor substrate. Then, a second conductive layer is formed on the other surface of the semiconductor substrate, and the first conductive layer and the second conductive layer are joined together. .

According to another aspect of the invention,
Producing a plurality of semiconductor chips;
Applying an insulation treatment to each of the semiconductor chips;
Laminating and stacking the semiconductor chips together;
With
In the step of manufacturing each semiconductor chip, a first conductive layer is formed from one surface to the middle of the side surface of the semiconductor substrate by discharging conductive ink droplets from the inkjet head to the semiconductor substrate. After that, a second conductive layer is formed from the other surface of the semiconductor substrate to the middle portion of the side surface, and the first conductive layer and the second conductive layer are connected to each other. A method for manufacturing a semiconductor device is provided.

According to another aspect of the invention,
A semiconductor device manufactured by the method for manufacturing a semiconductor device is provided.

According to another aspect of the invention,
A wiring forming apparatus for discharging conductive ink droplets from an inkjet head to a semiconductor substrate to form a wiring by a conductive layer,
Holding / reversing means for reversing while holding the semiconductor substrate;
An ink jet head for discharging conductive ink droplets to the semiconductor substrate;
A wiring forming apparatus is provided.

  According to the wiring forming method and the semiconductor device manufacturing method according to one aspect or the other aspect of the present invention, the conductive layer is formed from one surface of the semiconductor substrate (via the side surface) to the other surface. When stacking semiconductor chips formed with such conductive layers, stack the semiconductor chips so that the conductive layers of the semiconductor chips are in contact with the connection portions (electrodes, connection terminals, etc.) of other semiconductor chips. In this case, the semiconductor chips can be connected to each other.

  According to the wiring forming apparatus according to another aspect of the present invention, since the holding / reversing means is provided, first, the first conductive layer is formed from one surface to the side surface (or the middle portion of the side surface) of the front and back surfaces of the semiconductor substrate. After that, the semiconductor substrate is inverted, and a second conductive layer is formed on the other surface of the semiconductor substrate (or from the other surface to the middle of the side surface) to form the first conductive layer and the second conductive layer. The conductive layer can be connected. As a result, a conductive layer can be formed from one surface of the semiconductor substrate (via the side surface) to the other surface, and when the semiconductor chips formed with such a conductive layer are stacked, the semiconductor chip If the semiconductor chips are stacked so that the conductive layer is in contact with a connection portion (electrode, connection terminal, etc.) of another semiconductor chip, the semiconductor chips can be made conductive.

  Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings.

<First Embodiment>
[Semiconductor device]
As shown in FIG. 1, the semiconductor device 1 has three semiconductor chips 10 and has a configuration in which these are stacked. Each semiconductor chip 10 has the same configuration. The configuration of the uppermost semiconductor chip 10 will be described. The semiconductor chip 10 has a semiconductor substrate 12 (for example, a silicon substrate). An integrated circuit 11 (for example, a circuit having a transistor and a memory) and an electrode 14 (for example, a pad) are formed on the semiconductor substrate 12. The electrode 14 is electrically connected to the integrated circuit 11. The electrode 14 is made of an aluminum-based or copper-based metal, and has a rectangular surface shape.

Although not shown, at least one insulating film is formed on the semiconductor substrate 12. This insulating film is called a passivation film and is made of, for example, SiO ₂ , SiN, polyimide resin or the like, and the electrode 14 is exposed from the insulating film.

  A conductive layer 16 is formed on the semiconductor substrate 12. The conductive layer 16 extends from the front surface 12a of the semiconductor substrate 12 through the side surface 12b to the back surface 12c. The conductive layer 16 is a wiring having a linear shape, and one end thereof is connected to the electrode 14. The other end of the conductive layer 16 is a protruding portion formed integrally with the conductive layer 16, and the protruding portion serves as a connection terminal 18 and is electrically connected to the second-stage semiconductor chip 10 (the electrode 14 thereof). is doing. The conductive layer 16 is formed by drying the ink droplets R of the ink I ejected from the inkjet head (70) and further sintering the metal nanoparticles contained in the ink I (see later). .

  Note that the semiconductor device 1 may be mounted on the wiring board 20 and may be a semiconductor device. In this case, a wiring pattern 22 is formed on the wiring substrate 20, and the connection terminal 18 of the semiconductor chip 10 disposed at the bottom of the semiconductor chips 10 stacked in three stages is electrically connected to the wiring pattern 22.

  In the semiconductor device 1, the semiconductor chips 10 or the semiconductor chip 10 and the wiring board 20 are bonded to each other by the adhesive layer 30. The adhesive layer 30 is made of an insulating adhesive S.

[Wiring forming equipment]
Next, a wiring forming apparatus 40 used for forming the conductive layer 16 on the semiconductor substrate 12 will be described with reference to FIGS.

  As shown in FIG. 2, the wiring forming apparatus 40 has a rectangular work table 42. A pair of robot arms 50 are provided on the work table 42. A U-shaped holding part 52 for holding the semiconductor substrate 12 is provided at the tip of the robot arm 50 (see FIG. 3). The robot arm 50 is provided with three rotating portions 54. The robot arm 50 can be rotated with each rotation part 54 serving as a fulcrum (see the arrow in FIG. 2), and the holding part 52 moves in the front-rear direction, the left-right direction, and the up-down direction as each rotation part 54 rotates. It is supposed to be.

  As shown in FIG. 3, the semiconductor substrate 12 is sandwiched between the sandwiching portions 52 of the pair of robot arms 50. In a state where the semiconductor substrate 12 is sandwiched between the sandwiching portions 52, the conductive layer 16 is exposed from between the sandwiching portions 52. An alignment mechanism 56 is formed at the center of the sandwiching portion 52. The alignment mechanism 56 can rotate on the holding part 52 on a two-dimensional plane in the front-rear and left-right directions so that the position of the semiconductor substrate 12 can be finely adjusted on the two-dimensional plane in a state where the semiconductor substrate 12 is held. It has become.

  In the present embodiment, the semiconductor substrate 12 can be reversed while being held by holding the semiconductor substrate 12 by the holding portion 52 of the robot arm 50, and at least the holding / reversing means is held by the robot arm 50. Is configured. The term “clamping” is one form of “holding”, and, for example, a configuration in which the semiconductor substrate 12 is held by “sucking” the end surfaces (left and right side surfaces in FIG. 3) of the semiconductor substrate 12 instead of the clamping unit 52. May be adopted.

  As shown in FIG. 2, an inkjet head 70 is provided above the sandwiching portion 52 of the robot arm 50. A counter electrode 80 is provided at a position below the sandwiching portion 52 of the robot arm 50 and facing the inkjet head 70.

  The ink jet head 70 is supported by a gantry 60 as a support member. The gantry 60 is provided with a moving means (not shown) for moving the ink jet head 70, and the ink jet head 70 can be moved in the front-rear direction while being supported by the gantry 60 by the moving means. The inkjet head 70 has a plurality of nozzles (not shown). The ink jet head 70 discharges ink I having charging properties as ink droplets R downward from each nozzle (specifically, toward the semiconductor substrate 12 sandwiched by the sandwiching portion 52 of the robot arm 50). Yes.

  The counter electrode 80 is a flat plate that supports the semiconductor substrate 12, and is arranged in parallel to the ink ejection surface (lower surface) of the inkjet head 70 and separated by a predetermined distance. The separation distance between the inkjet head 70 and the counter electrode 80 is appropriately set within a range of about 0.1 to 5.0 mm. The counter electrode 80 is grounded and is always maintained at the ground potential. Therefore, when the charged ink droplet R lands on the semiconductor substrate 12 sandwiched by the sandwiching portion 52 of the robot arm 50, the counter electrode 80 can release the charge by grounding.

  The counter electrode 80 is provided with lifting / lowering means (not shown), and the counter electrode 80 can be moved in the vertical direction by the lifting / lowering means.

  As shown in FIG. 3, the inkjet head 70 is connected to the control means 90. The control means 90 is a computer composed of a CPU, ROM, RAM, and the like. The control unit 90 is connected to an electrostatic voltage power source 92 that applies a high-voltage electrostatic voltage to the inkjet head 70 and a piezoelectric element (not shown) provided in the inkjet head 70. The control means 90 controls the electrostatic voltage power source 92 to apply an electrostatic voltage to the ink jet head 70, thereby generating an electrostatic field between the ink jet head 70 and the counter electrode 80, and the deformation of the piezoelectric element. And the ink droplets R are ejected from the ink jet head 70, respectively. The voltage applied by the electrostatic voltage power source 92 is basically a direct current, but may be an alternating current. In the present embodiment, at least the control means 90 and the electrostatic voltage power source 92 constitute voltage application means.

  Ink I is an ink having conductivity and chargeability by dispersing metal nanoparticles. Examples of the metal nanoparticles include silver, gold, copper, palladium, platinum, nickel, rhodium, tin, indium, and alloys thereof.

  There are two main methods for producing such metal nanoparticles. One is the physical method and the other is the chemical method. The physical method is generally a method for producing nanoparticles by pulverizing bulk metal, and the chemical method is a method for producing nanoparticles by generating metal atoms and controlling their aggregation.

  The chemical method is roughly classified into a wet method performed in a liquid and a dry method performed in air or in a reduced pressure atmosphere. The chemical reduction method, which is well known as a wet method, is a technique in which a reducing agent is added to a metal ion solution or a metal salt solution containing a reducing agent is heated to reduce metal ions to generate nanoparticles. is there. As the ink in which such nanoparticles are dispersed, for example, the ink disclosed in Japanese Patent No. 3933138 can be used. A gas evaporation method is known as a dry method. The gas evaporation method is a method in which a metal is evaporated in an inert gas and then cooled and aggregated by collision with the gas to generate nanoparticles. It is known that the particle size of the dry method can be made smaller than that of the wet method, and nanoparticles having a particle size of about several nm can be generated by the dry method.

  The particle size of the metal nanoparticles in the ink I used in the present embodiment is 1 to 100 nm, preferably 1 to 50 nm. Although metal nanoparticles having a particle size of less than 1 nm may be used, such particles are extremely difficult to produce and are not practical. Further, when metal nanoparticles having a particle size exceeding 100 nm are used, the nozzles of the inkjet head 70 may be clogged.

  The concentration of the metal nanoparticles dispersed in the ink I is preferably high so that the resistance value of the conductive layer 16 formed by drying the ink I becomes closer to the resistance value of the electrode 14. . Specifically, 10 wt% or more is preferable, and 20 wt% is more preferable. However, the concentration of the metal nanoparticles can be about 80 wt% at the maximum.

  As the solvent for dispersing the metal nanoparticles in the ink I, water or a water-soluble organic solvent is used. Such a so-called water-based ink is superior in electric conductivity as compared with an oil-based ink using a nonpolar solvent. Further, this solvent preferably has a low vapor pressure and a high boiling point so that the viscosity of the ink I does not easily rise or dry. As a boiling point of a solvent, 150 degreeC or more is preferable and 200 degreeC or more is more preferable. The water content is preferably 40 wt% or less from the viewpoint of drying properties.

  The viscosity of the ink I is preferably 2 mPa · s or more and 10 mPa · s or less at the discharge temperature, more preferably 3 mPa · s or more and 6.5 mPa · s or less. About discharge temperature, 20-60 degreeC is preferable and 25-50 degreeC is more preferable. This is because if it is less than 25 ° C., cooling may be required, and if it exceeds 50 ° C., the inkjet head 70 and the flow path member of the ink I may be burdened.

  The surface tension of the ink I is preferably 20 mN / m or more and 50 mN / m or less. Furthermore, from the viewpoint of ejection stability, it is more preferably 25 mN / m or more and 45 mN / m or less.

The electrical conductivity of the ink I is preferably 0.1 μS / cm or more and 2000 μS / cm or less at 25 ° C. in order to apply an electrostatic attraction force. However, from the viewpoint of high-definition drawing, 1 μS / cm or more and 1000 μS / cm More preferable is cm or less.
The relative dielectric constant of the ink I is preferably 10 or more.

[Wiring formation method]
Next, a method for manufacturing the semiconductor device 1, which mainly forms the conductive layer 16 on the semiconductor substrate 12 using the wiring forming device 40, will be described with reference to FIG. 4.

  The semiconductor substrate 12 on which the integrated circuit 11 and the electrode 14 are formed in advance is supported by the counter electrode 80 while being sandwiched by the sandwiching portion 52 of the robot arm 50, and the inkjet head 70 is disposed above the electrode 14. Thereafter, a voltage is applied to the inkjet head 70 to form a predetermined potential difference between the inkjet head 70 and the counter electrode 80 (generate lines of electric force).

  Thereafter, as shown in FIG. 4A, the ink jet head 70 is moved while ejecting ink droplets R from the ink jet head 70, and the conductive layer 16 is formed from the surface 12 a to the side surface 12 b of the semiconductor substrate 12. In this case, since a potential difference is generated between the ink jet head 70 and the counter electrode 80, an electrostatic attractive force is generated between the ink droplet R and the semiconductor substrate 12, and the ink droplet R is side-surfaced from the surface 12 a of the semiconductor substrate 12. Landing continuously over 12b.

  Thereafter, the rotation part 54 of the robot arm 50 (the rotation part 54 at the base end of the clamping part 52) is rotated to invert the semiconductor substrate 12, and the original state (the semiconductor substrate 12 is supported by the counter electrode 80). , A state in which a voltage is applied to the inkjet head 70. Thereafter, as shown in FIG. 4B, the ink-jet head 70 is moved while ejecting ink droplets R from the ink-jet head 70, and the conductive layer 16 is also formed on the back surface 12 c of the semiconductor substrate 12. In this case, the conductive layer 16 previously formed in the step of FIG. 4A and the conductive layer 16 formed on the back surface 12c are joined together.

  4A, the conductive layer 16 is formed only on the surface 12a of the semiconductor substrate 12, and then the conductive layer 16 is formed from the back surface 12c to the side surface 12b of the semiconductor substrate 12 in the step of FIG. 4B. However, the conductive layer 16 formed earlier and the conductive layer 16 formed later may be joined together.

  Furthermore, as shown in FIG. 5, the conductive layer 16 is formed from the front surface 12a of the semiconductor substrate 12 to the middle portion of the side surface 12b in the previous step (see FIG. 5A), and in the subsequent steps, the back surface of the semiconductor substrate 12 is formed. The conductive layer 16 is formed from 12c to the middle portion of the side surface 12b (see FIG. 5B), and the conductive layer 16 formed earlier and the conductive layer 16 formed later are joined on the side surface 12b of the semiconductor substrate 12. Also good.

  Thereafter, as shown in FIG. 4C, the ink jet head 70 is stopped at a position facing the electrode 14 of the semiconductor substrate 12, and a plurality of ink droplets R are ejected from the ink jet head 70 at that position. The connection terminal 18 is formed by thickening the portion with the ink droplet R.

  Here, an example is shown of a case where the number of conductive layers 16 in the semiconductor substrate 12 is small and can be handled by one inkjet head 70 (see FIG. 3). However, as shown in FIG. When a plurality of integrated circuits 11 are arranged in the substrate 12 and the number of conductive layers 16 is large, a plurality of inkjet heads 70 corresponding to the number of conductive layers 16 are arranged in parallel, and FIGS. The conductive layer 16 can be formed in the same manner as described with reference to c).

  Thereafter, the semiconductor substrate 12 is removed from the holding portion 52 of the robot arm 50, and the conductive layer 16 of the semiconductor substrate 12 is baked. Examples of the firing method include sintering in a dryer or a hot plate. In this embodiment, preferably, in order to control the wettability of the ink I and improve the adhesion elasticity, an undercoat agent (a silane coupling agent or a titanium coupling agent) is applied to the semiconductor substrate 12 and various cups are applied. Sintering is performed under conditions that ensure the heat resistance of the ring agent.

  In this sintering, it is preferable to perform main sintering at 150 to 200 ° C. for 60 to 180 minutes after preliminary drying at 100 to 150 ° C. for 10 to 30 minutes. If the preliminary drying is not performed, the solvent remains in the fused metal, and the resistance value may increase. When the temperature of the preliminary drying is 100 ° C. or lower, the solvent hardly evaporates and there is a possibility that the effect does not occur. When the sintering temperature is 150 ° C. or lower, the metal nanoparticles are not fused, and the resistance value may be increased. When the sintering temperature is 200 ° C. or higher, the subbing agent is deteriorated and mixed with the fusion metal, resulting in a resistance value of There is a risk of becoming higher. A hot plate is preferably used for the main sintering. This is because when the hot plate is used, heat is directly transmitted to the ink I, and the fusion of the metal nanoparticles is facilitated. By such baking, the solvent of the ink droplet R evaporates, and the conductive layer 16 is fixed to the semiconductor substrate 12.

  And the process of the above process is repeatedly performed and the three semiconductor chips 10 are formed. Thereafter, each semiconductor chip 10 is insulated. Specifically, as shown in FIG. 4D, the adhesive S is applied to the back surface 12c of the semiconductor substrate 12 for each semiconductor chip 10, and the adhesive layer 30 is formed on the back surface 12c. In this case, the connection terminals 18 of the semiconductor chip 10 are masked, and the connection terminals 18 are exposed from the adhesive layer 30. In the insulation process, instead of using the adhesive S, an insulating adhesive sheet may be attached to the back surface 12c of the semiconductor substrate 12. Even in this case, the connection terminal 18 is exposed from the adhesive sheet.

  Thereafter, as shown in FIG. 4E, the three semiconductor chips 10 are stacked and the three semiconductor chips 10 are bonded to each other. In this case, each semiconductor chip 10 is positioned so that the connection terminal 18 of the semiconductor chip faces the electrode 14 of the other semiconductor chip 10. The semiconductor device 1 can be manufactured through the above steps.

  When the semiconductor device 1 is mounted on the wiring substrate 20, as shown in FIG. 4F, the wiring pattern 22 is opposed to the connection terminal 18 of the semiconductor chip 10 arranged at the top, so that the semiconductor chip 10 The three-layered laminate and the wiring board 20 may be bonded together.

  According to the above-described embodiment, when the semiconductor chip 10 is manufactured, the conductive layer 16 is formed from the front surface 12 a to the side surface 12 b of the semiconductor substrate 12, and then the semiconductor substrate 12 is inverted to form the back surface 12 c of the semiconductor substrate 12. Since the conductive layer 16 is formed, as a result, the conductive layer 16 can be formed from the front surface 12a of the semiconductor substrate 12 (through the side surface 12b) to the back surface 12c (see FIGS. 4A to 4C). .

  Then, when the semiconductor device 1 is manufactured by stacking the semiconductor chips 10, the connection terminals 18 of one semiconductor chip 10 are bonded while facing the electrodes 14 of the other semiconductor chip 10. The semiconductor chips 10 can be electrically connected to each other in the semiconductor device 1 as a result (see FIGS. 4D to 4E).

[Modification]
As shown in FIG. 7, in the wiring device 40 according to the first embodiment, the inkjet head 70 is grounded, and an electrostatic voltage power source 92 is connected to the counter electrode 80, so that the inkjet head 70 is connected to the counter electrode 80. An electrostatic field may be generated. In this case, the inkjet head 70 side has a low voltage, and the counter electrode 80 side has a high voltage.

<Second Embodiment>
The second embodiment is different from the first embodiment mainly in the following points, and is otherwise the same as the first embodiment.

  As shown in FIG. 8, in the wiring forming apparatus 40 according to the second embodiment, the counter electrode 80 is not provided, and instead, the holding portion 52 of the robot arm 50 has the function. That is, an electrostatic voltage power source 92 is provided in the vicinity of the robot arm 50, and the electrostatic voltage power source 92 is connected to the holding unit 52 via the cable 94. A cable socket 58 (see FIG. 3) is provided in the clamping unit 52, and a cable 94 is connected to the cable socket 58, and a voltage is applied to the clamping unit 52 from the electrostatic voltage power source 92.

  When the conductive layer 16 is formed on the semiconductor substrate 12, the semiconductor substrate 12 on which the integrated circuit 11 and the electrode 14 are formed is supported while being sandwiched by the sandwiching portion 52 of the robot arm 50, and the inkjet head 70 is supported by the electrode 14. It arranges above. Thereafter, a voltage is applied to the sandwiching section 52 of the robot arm 50 to form a predetermined potential difference between the sandwiching section 52 and the inkjet head 70 (generate lines of electric force).

  Thereafter, as shown in FIG. 9A, the inkjet head 70 is moved while ejecting ink droplets R from the inkjet head 70, and the conductive layer 16 is formed from the surface 12 a to the side surface 12 b of the semiconductor substrate 12. In this case, since a potential difference is generated between the sandwiching portion 52 (specifically, the semiconductor substrate 12 sandwiched by the sandwiching portion 52) and the inkjet head 70, an electrostatic attractive force is generated between the ink droplet R and the semiconductor substrate 12. As a result, the ink droplet R is continuously landed from the surface 12 a to the side surface 12 b of the semiconductor substrate 12.

  Thereafter, the application of the voltage to the clamping unit 52 of the robot arm 50 is released, the rotating unit 54 (the rotating unit 54 at the proximal end of the clamping unit 52) is rotated, and the semiconductor substrate 12 is inverted, so that the original The state is returned (a state where a voltage is applied to the clamping unit 52). Thereafter, as shown in FIG. 9B, the ink-jet head 70 is moved while ejecting ink droplets R from the ink-jet head 70, and the conductive layer 16 is also formed on the back surface 12 c of the semiconductor substrate 12. In this case, the conductive layer 16 previously formed in the step of FIG. 9A and the conductive layer 16 formed on the back surface 12c are joined together.

  Also in this case, the conductive layer 16 is formed only on the surface 12a of the semiconductor substrate 12 in the step of FIG. 9A, and then in the step of FIG. 9B, the conductive layer is formed from the back surface 12c to the side surface 12b of the semiconductor substrate 12. 16 may be formed, and the conductive layer 16 formed earlier may be connected to the conductive layer 16 formed later.

  Of course, the conductive layer 16 is formed from the front surface 12a of the semiconductor substrate 12 to the middle portion of the side surface 12b in the step of FIG. 9A, and then the back surface 12c of the semiconductor substrate 12 to the side surface 12b in the step of FIG. The conductive layer 16 may be formed in the middle, and the conductive layer 16 formed earlier and the conductive layer 16 formed later may be connected to each other at the side surface 12 b of the semiconductor substrate 12.

  Thereafter, as shown in FIG. 9C, the inkjet head 70 is stopped at a position facing the electrode 14 of the semiconductor substrate 12, and a plurality of ink droplets R are ejected from the inkjet head 70 at that position. The connection terminal 18 is formed by thickening the portion with the ink droplet R. Thereby, the semiconductor chip 10 is manufactured.

  Also according to this embodiment, the conductive layer 16 can be formed from the front surface 12a of the semiconductor substrate 12 (through the side surface 12b) to the back surface 12c (see FIGS. 9A to 9C). When manufacturing the semiconductor device 1 by stacking the chips 10, the electrodes 14 of the respective semiconductor chips 10 are electrically connected to each other, and as a result, the semiconductor chips 10 can be made conductive in the semiconductor device 1.

[Modification]
As shown in FIG. 10, in the wiring forming apparatus 40 according to the second embodiment, the clamping unit 52 of the robot arm 50 is grounded, and the electrostatic voltage power source 92 is connected to the inkjet head 70 so as to clamp the inkjet head 70. An electrostatic field may be generated between the part 52 and the part 52. In this case, the clamping unit 52 side has a low voltage, and the inkjet head 70 side has a high voltage.

It is sectional drawing which shows schematic structure of the semiconductor device concerning preferable embodiment of this invention. 1 is a perspective view schematically showing an overall configuration of a wiring forming apparatus according to a preferred embodiment (first embodiment) of the present invention. FIG. 4 is a perspective view schematically showing a part of the wiring forming apparatus of FIG. 3. It is drawing for demonstrating roughly each process of the manufacturing method of the semiconductor device concerning 1st Embodiment. It is drawing which shows the modification of the one part process of FIG. It is a perspective view which shows the modification of FIG. It is a perspective view which shows the modification of FIG. It is a perspective view which shows roughly the whole structure of the wiring formation apparatus concerning preferable embodiment (2nd Embodiment) of this invention. It is drawing for demonstrating roughly each process of the manufacturing method of the semiconductor device concerning 2nd Embodiment. It is drawing which shows the modification of FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Semiconductor device 10 Semiconductor chip 12 Semiconductor substrate 12a Front surface 12b Side surface 12c Back surface 14 Electrode 16 Conductive layer 18 Connection terminal 20 Wiring board 22 Wiring pattern 30 Adhesive layer 40 Wiring forming device 42 Work table 50 Robot arm 52 Holding part 54 Turning part 56 Alignment mechanism 58 Cable socket 60 Gantry 70 Inkjet head 80 Counter electrode 90 Control means 92 Electrostatic voltage power supply 94 Cable I Ink R Ink droplet S Adhesive

Claims (11)

A wiring formation method for forming a wiring by a conductive layer by discharging conductive ink droplets from an inkjet head to a semiconductor substrate,
Forming a first conductive layer from one side to the side of the front and back sides of the semiconductor substrate;
Forming a second conductive layer on the other surface of the semiconductor substrate and joining the first conductive layer and the second conductive layer;
A wiring formation method comprising: A wiring formation method for forming a wiring by a conductive layer by discharging conductive ink droplets from an inkjet head to a semiconductor substrate,
Forming a first conductive layer from one of the front and back surfaces of the semiconductor substrate to the middle of the side surface;
Forming a second conductive layer from the other surface of the semiconductor substrate to the middle portion of the side surface, and joining the first conductive layer and the second conductive layer;
A wiring formation method comprising: In the wiring formation method according to claim 1 or 2,
A wiring forming method, wherein an electrostatic attractive force is generated between the ink droplet and the semiconductor substrate. Producing a plurality of semiconductor chips;
Applying an insulation treatment to each of the semiconductor chips;
Laminating and stacking the semiconductor chips together;
With
In the process of manufacturing each semiconductor chip, a first conductive layer is formed from one surface to the side surface of the semiconductor substrate by discharging conductive ink droplets from the inkjet head to the semiconductor substrate. Then, a second conductive layer is formed on the other surface of the semiconductor substrate, and the first conductive layer and the second conductive layer are joined together. Producing a plurality of semiconductor chips;
Applying an insulation treatment to each of the semiconductor chips;
Laminating and stacking the semiconductor chips together;
With
In the step of manufacturing each semiconductor chip, a first conductive layer is formed from one surface to the middle of the side surface of the semiconductor substrate by discharging conductive ink droplets from the inkjet head to the semiconductor substrate. After that, a second conductive layer is formed from the other surface of the semiconductor substrate to the middle portion of the side surface, and the first conductive layer and the second conductive layer are connected to each other. A method for manufacturing a semiconductor device. In the manufacturing method of the semiconductor device according to claim 4 or 5,
A method of manufacturing a semiconductor device, wherein electrostatic attraction is generated between the ink droplets and the semiconductor substrate. In the manufacturing method of the semiconductor device according to any one of claims 4 to 6,
A method of manufacturing a semiconductor device, wherein an insulating adhesive is applied to each semiconductor chip in the step of applying an insulation treatment to each semiconductor chip.   A semiconductor device manufactured by the method for manufacturing a semiconductor device according to claim 4. A wiring forming apparatus for discharging conductive ink droplets from an inkjet head to a semiconductor substrate to form a wiring by a conductive layer,
Holding / reversing means for reversing while holding the semiconductor substrate;
An ink jet head for discharging conductive ink droplets to the semiconductor substrate;
A wiring forming apparatus comprising: The wiring forming apparatus according to claim 9, wherein
A counter electrode disposed to face the inkjet head and supporting the semiconductor substrate;
Voltage applying means for applying a voltage between the inkjet head and the counter electrode;
A wiring forming apparatus comprising: The wiring forming apparatus according to claim 9, wherein
A wiring forming apparatus comprising voltage applying means for applying a voltage between the holding / reversing means and the inkjet head.

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