JP6644522B2 - Method for manufacturing semiconductor device - Google Patents

Description

  The present invention relates to a method for manufacturing a semiconductor device such as a thermoelectric conversion device.

  A full skeleton type thermoelectric converter and a half skeleton type thermoelectric converter are known. Both types of thermoelectric converters are more reliable than sandwich type thermoelectric converters. The sandwich type may be damaged due to a difference in linear expansion between a pair of substrates, but the full skeleton type has no substrate and the half skeleton type has only one substrate.

  Incidentally, a step of joining one end of the semiconductor element and the first electrode by reflow (hereinafter, referred to as a “first joining step”) and a step of joining the other end of the semiconductor element and the second electrode by reflow (hereinafter, “first joining step”). 2 bonding step ") is performed individually to obtain a thermoelectric conversion device.

JP-A-11-307825

  However, the method of individually performing the first bonding step and the second bonding step requires a lot of man-hours. An object of the present invention is to provide a method for manufacturing a semiconductor device, which can reduce the number of steps as compared with a method in which the first bonding step and the second bonding step are individually performed.

  The present invention includes a step of fixing a first end of a semiconductor element to a first electrode disposed on a first carrier with a first joining member, and a step of fixing a second end of the semiconductor element to a second electrode disposed on a second carrier. The present invention relates to a method for manufacturing a semiconductor device including a step of fixing an end with a second joining member and a step of sintering the first joining member and the second joining member. The method for manufacturing a semiconductor device according to the present invention can reduce the number of steps compared to a method in which the first bonding step and the second bonding step are individually performed. It is preferable that at least one of the first carrier and the second carrier disappears in the step of performing sintering. This is because a skeleton structure—a full skeleton or a half skeleton—can be formed in the sintering process.

FIG. 3 is a schematic sectional view of a sintering step in the method according to the first embodiment. It is a schematic sectional drawing of a 1st electrode mounting support body. It is a schematic sectional drawing of the manufacturing process of a 1st electrode mounting support body. It is a schematic sectional drawing of the manufacturing process of a 1st electrode mounting support body. It is a schematic sectional drawing of the manufacturing process of a 1st electrode mounting support body. It is a schematic sectional drawing of the manufacturing process of a 1st electrode mounting support body. It is a schematic sectional drawing of the manufacturing process of a 1st electrode mounting support body. It is a schematic sectional drawing of the manufacturing process of a 1st electrode mounting support body. It is a schematic sectional drawing of the manufacturing process of a 1st electrode mounting support body. It is a schematic sectional drawing of the manufacturing process of a 1st electrode mounting support body. It is a schematic sectional drawing of the 1st electrode mounting support body after a 1st carrier fixation. It is a schematic sectional drawing of the 1st electrode mounting carrier. It is a schematic sectional drawing of the 2nd electrode mounting carrier. It is a schematic sectional drawing of the manufacturing process of a 1st chip. It is a schematic sectional drawing of the manufacturing process of a 1st chip. It is a schematic sectional drawing of the manufacturing process of a 2nd chip. It is a schematic sectional drawing of the manufacturing process of a 2nd chip. It is a schematic sectional drawing of the manufacturing process of a joint body. It is a schematic sectional drawing of the manufacturing process of a joint body. It is a schematic sectional drawing of a sintering process. FIG. 3 is a schematic sectional view of a semiconductor device. FIG. 15 is a schematic cross-sectional view of a manufacturing step of a first chip in Modification Example 3. FIG. 15 is a schematic cross-sectional view of a manufacturing step of a second chip in Modification Example 4.

  Hereinafter, the present invention will be described in detail with reference to embodiments, but the present invention is not limited to these embodiments.

[Embodiment 1]
As shown in FIG. 1, in the method for manufacturing a semiconductor device according to the first embodiment, a step of fixing a first end of a semiconductor element 151 to a first electrode 112 a arranged on a first carrier 113 with a first bonding member 152. Fixing the second end of the semiconductor element 151 to the second electrode 122a disposed on the second carrier 123 with the second joint member 153, and sintering the first joint member 152 and the second joint member 153. Performing the steps. The manufacturing method of the semiconductor device according to the first embodiment can reduce the number of steps as compared with the method in which the first bonding step and the second bonding step are individually performed. In the method for manufacturing a semiconductor device according to the first embodiment, a full skeleton structure can be formed in a step of performing sintering. This is because the first carrier 113 and the second carrier 123 disappear in the sintering process.

  As shown in FIG. 2, a first electrode mounting support 110 is prepared. The first electrode mounting support 110 includes a first support 111 and first electrodes 112a, 112b, and 112c provided on the first support 111 (hereinafter, may be collectively referred to as "first electrodes 112"). including. The first support 111 is a metal plate such as a stainless steel (SUS) plate, for example. The SUS plate is preferable because it is easily peeled off from the first electrode 112. Both surfaces of the first support 111 can be defined by a first surface and a second surface facing the first surface. The first electrode 112 is made of, for example, a metal such as copper. In order to obtain the first electrode mounting support 110, a film 114 is prepared as shown in FIG. 3A, an opening is formed in the film 114 with a Thomson blade, a laser or the like as shown in FIG. 3B, and as shown in FIG. 3C. 3D, a film 114 is disposed on the first surface of the first support 111, and a film 115 is disposed on the second surface of the first support 111 as necessary, as shown in FIG. 3D. The procedure of forming the first electrodes 112a, 112b, 112c on the first surface of the first support 111 by electroplating can be adopted. On the other hand, in order to obtain the first electrode mounting support 110, a photosensitive resin film 117 is disposed on the first surface of the first support 111 as shown in FIG. 4B, the photosensitive resin film 117 is selectively exposed to light as shown in FIG. 4B, and is developed by electroplating as shown in FIG. 4C. A procedure for forming the first electrodes 112a, 112b, 112c on the surface can also be adopted.

  As shown in FIG. 5, the first carrier 113 is fixed to the first electrodes 112a, 112b, 112c. The first carrier 113 has a property of being decomposed by heat. That is, the first carrier 113 has a property of disappearing by the heat of sintering. The first carrier 113 is made of a resin that causes thermal decomposition. For example, acrylic resin or polycarbonate. The first carrier 113 can have a plate shape, a sheet shape, and a film shape, for example.

  As shown in FIG. 6, the first support 111 is peeled off from the first electrodes 112a, 112b, 112c to obtain the first electrode mounting carrier 11. The first electrode mounting carrier 11 includes a first carrier 113 and first electrodes 112a, 112b, 112c arranged on the first carrier 113.

  As shown in FIG. 7, the second electrode mounting carrier 12 is prepared. The second electrode-mounted carrier 12 includes a second carrier 123 and second electrodes 122a, 122b, and 122c (hereinafter, may be collectively referred to as a “second electrode 122”) disposed on the second carrier 123. The description of the composition of the second carrier 123 is omitted. This is because the composition of the second carrier 123 is the same as the composition of the first carrier 113. The second electrode 122 is made of, for example, a metal such as copper. The second electrode mounting carrier 12 can be manufactured by the same method as the manufacturing method of the first electrode mounting carrier 11.

  As shown in FIG. 8, a pre-press laminate 14 is prepared. The pre-press laminate 14 includes a first semiconductor wafer 141, a first pre-dicing bonding member 142, and a second pre-dicing bonding member 143. Both surfaces of the first semiconductor wafer 141 are defined by a first main surface and a second main surface facing the first main surface. The first pre-dicing bonding member 142 is located on the first main surface of the first semiconductor wafer 141. The first pre-dicing joining member 142 has a property of becoming a sintered body by heating. The first pre-dicing joining member 142 has a sheet shape. The second pre-dicing bonding member 143 is located on the second main surface of the first semiconductor wafer 141. The second pre-dicing joining member 143 has a property of becoming a sintered body by heating. The second pre-dicing joining member 143 has a sheet shape. A laminate is obtained by pressing the laminate 14 before pressing. Specifically, a laminate is obtained by heating the pre-press laminate 14 while applying a force to the pre-press laminate 14 with a pair of substantially parallel flat plates 911 and 912. The temperature is, for example, 23C to 150C, preferably 40C to 90C. The stacked body includes a first semiconductor wafer 141, a first pre-dicing bonding member 142 fixed to a first main surface of the first semiconductor wafer 141, and a second semiconductor member fixed to a second main surface of the first semiconductor wafer 141. And a joining member 143 before dicing.

As shown in FIG. 9, first chips 15a, 15b, 15c, 15d, and 15e (hereinafter, may be collectively referred to as “first chips 15”) are formed by dicing the stacked body. Specifically, the laminate is fixed to a dicing sheet, and the laminate is cut with a dicing blade or the like. Each first chip 15 includes a first semiconductor element 151, a first bonding member 152, and a second bonding member 153. The first semiconductor element 151 is a first conductivity type thermoelectric conversion element. For example, semiconductor elements such as Bi ₂ Te ₃ , oxide semiconductor, silicide, skutterudite, Heusler, and carbon / polymer materials can be used. Both ends of the first semiconductor element 151 are defined by a first end and a second end facing the first end. The first joining member 152 is fixed to a first end of the first semiconductor element 151. The second joining member 153 is fixed to the second end of the first semiconductor element 151.

  As shown in FIG. 10, a pre-press laminate 16 is prepared. The pre-press laminate 16 includes a second semiconductor wafer 161, a first pre-dicing bonding member 162, and a second pre-dicing bonding member 163. Both surfaces of the second semiconductor wafer 161 are defined by a first main surface and a second main surface facing the first main surface. The first pre-dicing bonding member 162 is located on the first main surface of the second semiconductor wafer 161. The first pre-dicing joining member 162 has a property of becoming a sintered body by heating. The first pre-dicing joining member 162 has a sheet shape. The second pre-dicing bonding member 163 is located on the second main surface of the second semiconductor wafer 161. The second pre-dicing joining member 163 has a property of becoming a sintered body by heating. The second pre-dicing joining member 163 has a sheet shape. A laminate is obtained by pressing the laminate 16 before pressing. Specifically, a laminate is obtained by heating the pre-press laminate 16 while applying force to the pre-press laminate 16 with a pair of substantially parallel flat plates 911 and 912. The temperature is, for example, 23C to 150C, preferably 40C to 90C. The stacked body includes a second semiconductor wafer 161, a first pre-dicing bonding member 162 fixed to the first main surface of the second semiconductor wafer 161, and a second semiconductor wafer 161 fixed to the second main surface of the second semiconductor wafer 161. And a joining member 163 before dicing.

As shown in FIG. 11, the laminate is diced to form second chips 17a, 17b, 11c, 11d, and 11e (hereinafter, may be collectively referred to as "second chips 17"). Specifically, the laminate is fixed to a dicing sheet, and the laminate is cut with a dicing blade or the like. Each second chip 17 includes a second semiconductor element 171, a first bonding member 172, and a second bonding member 173. The second semiconductor element 171 is a second conductivity type thermoelectric conversion element. For example, semiconductor elements such as Bi ₂ Te ₃ , oxide semiconductor, silicide, skutterudite, Heusler, and carbon / polymer materials can be used. Both ends of the second semiconductor element 171 are defined by a first end and a second end facing the first end. The first joining member 172 is fixed to a first end of the second semiconductor element 171. The second joining member 173 is fixed to the second end of the second semiconductor element 171.

  As shown in FIG. 12, the first chip 15a is pressed on the first region of the first electrode 112a. That is, the first end of the first semiconductor element 151 is fixed to the first region of the first electrode 112a by the first joining member 152. The pressure bonding is performed, for example, at 23 ° C to 150 ° C, preferably at 40 ° C to 90 ° C. Thereafter, the first chip 15b is crimped on the first region of the first electrode 112b, and the first chip 15c is crimped on the first region of the first electrode 112c. Since the first chip 15 is fixed to the first electrode 112, the first chip 15 is less likely to be displaced.

  The second chip 17a is pressure-bonded to the second region of the first electrode 112a. That is, the first end of the second semiconductor element 171 is fixed to the second region of the first electrode 112a by the first joining member 172. The pressure bonding is performed, for example, at 23 ° C to 150 ° C, preferably at 40 ° C to 90 ° C. Thereafter, the second chip 17b is pressure-bonded to the second region of the first electrode 112b. Since the second chip 17 is fixed to the first electrode 112, the second chip 17 is less likely to be displaced.

  As shown in FIG. 13, the second electrode-mounted carrier 12 is crimped to an aggregate including the first electrode-mounted carrier 11, the plurality of first chips 15, and the plurality of second chips 17. The pressure bonding is performed, for example, at 23 ° C to 150 ° C, preferably at 40 ° C to 90 ° C. The joint body 19 obtained by crimping includes a first carrier 113, a second carrier 123, a first chip 15a, a second chip 15b, a first electrode 112a, and second electrodes 122a and 122b. The first chip 15a connects the first region of the first electrode 112a and the second electrode 122a. The second chip 17a connects the second region of the first electrode 112a and the second electrode 122b.

  As shown in FIG. 14, the first joining members 152 and 172 and the second joining members 153 and 173 are sintered. Specifically, the combined body 19 is heated while applying force to the combined body 19 with a pair of substantially parallel flat plates 921 and 922. The lower limit of the sintering temperature is, for example, 180 ° C and 200 ° C. The upper limit of the sintering temperature is, for example, 350 ° C and 400 ° C. In the sintering process, the first carrier 113 and the second carrier 123 are decomposed, and the first carrier 113 and the second carrier 123 disappear.

  As shown in FIG. 15, the semiconductor device obtained by the above method includes a first electrode 112a, a second electrode 122a, and a first semiconductor element 151. The semiconductor device further includes a first post-sintering bonding member 156 and a second post-sintering bonding member 157. The first post-sintering bonding member 156 connects the first end of the first semiconductor element 151 and the first region of the first electrode 112a. The second post-sintering joining member 157 connects the second end of the first semiconductor element 151 and the second electrode 122a. The semiconductor device further includes a second semiconductor element 171 and a second electrode 122b. The semiconductor device further includes a first post-sintering bonding member 176 and a second post-sintering bonding member 177. The first post-sintering bonding member 176 connects the first end of the second semiconductor element 171 and the second region of the first electrode 112a. The second post-sintering joining member 177 connects the second end of the second semiconductor element 171 and the second electrode 122b. The semiconductor device can be used, for example, as a thermoelectric conversion device. Specifically, it is a skeleton type thermoelectric converter. When the first semiconductor element 151 is a p-type semiconductor element, the second semiconductor element 171 is n-type. When the first semiconductor element 151 is n-type, the second semiconductor element 171 is p-type.

  Hereinafter, the first joining members 152 and 172 and the second joining members 153 and 173 are collectively referred to as “joining members”. The joining member has a property of becoming a sintered body by heating. The joining member includes a binder having a property of being thermally decomposed by sintering (hereinafter, referred to as “a thermally decomposable binder”) and particles of a metal compound. The joining member further includes a binder having a boiling point of 100 ° C. to 350 ° C. (hereinafter, referred to as “low boiling point binder”).

  The thermally decomposable binder has, for example, the property that the carbon concentration after heating from 23 ° C. to 400 ° C. at a temperature increasing rate of 10 ° C./min in an air atmosphere shows 15% by weight or less. The carbon concentration can be measured by energy dispersive X-ray analysis. The thermally decomposable binder is preferably solid at 23 ° C. When the solid is formed at 23 ° C., the joining member can be easily formed. The thermally decomposable binder is, for example, polycarbonate, acrylic polymer, ethyl cellulose, polyvinyl alcohol and the like. The joining member may include one or more thermally decomposable binders.

  The lower limit of the average particle diameter of the particles of the metal compound is, for example, 0.05 nm, 0.1 nm, and 1 nm. The upper limit of the average particle size of the metal compound particles is, for example, 1000 nm and 100 nm. D50 data obtained by measurement in a standard mode using a particle size distribution measuring device (Microtrac HRA manufactured by Nikkiso Co., Ltd.) is defined as an average particle size. Examples of the metal compound include silver, copper, silver oxide, and copper oxide. These may be covered with an organic compound or the like. The joining member may include one or more metal particles.

  The low boiling binder is preferably liquid at 23 ° C. Examples of the low boiling point binder include pentanol, hexanol, heptanol, octanol, 1-decanol, ethylene glycol, diethylene glycol, propylene glycol, butylene glycol, α-terpineol, 1,6-hexanediol, isobornylcyclohexanol (MTPH), and the like. Monohydric and polyhydric alcohols, ethylene glycol butyl ether, ethylene glycol phenyl ether, diethylene glycol methyl ether, diethylene glycol ethyl ether, diethylene glycol butyl ether, diethylene glycol isobutyl ether, diethylene glycol hexyl ether, triethylene glycol methyl ether, diethylene glycol dimethyl ether, diethylene glycol diethyl ether Diethylene glycol dibutyl ether, diethylene glycol butyl methyl ether, diethylene glycol isopropyl methyl ether, triethylene glycol dimethyl ether, triethylene glycol butyl methyl ether, propylene glycol propyl ether, dipropylene glycol methyl ether, dipropylene glycol ethyl ether, dipropylene glycol propyl ether, Ethers such as propylene glycol butyl ether, dipropylene glycol dimethyl ether, tripropylene glycol methyl ether, tripropylene glycol dimethyl ether, ethylene glycol ethyl ether acetate, ethylene glycol butyl ether acetate, diethylene glycol ethyl ether Seteto is diethylene glycol butyl ether acetate, dipropylene glycol methyl ether acetate (DPMA). The joining member can include one or more low boiling binders.

(Modification 1)
In the first modification, the first carrier 113 does not disappear during the sintering process. In the first modification, the first carrier 113 is separated from the first electrodes 112a, 112b, and 112c as necessary after the sintering step.

(Modification 2)
In the second modification, the second carrier 123 does not disappear during the sintering process. In the second modification, the second carrier 123 is separated from the second electrodes 122a, 122b, 122c as necessary after the sintering step.

(Modification 3)
As shown in FIG. 16, in Modification 3, the pre-press laminate 14 further includes a first release liner 146 and a second release liner 147. The first semiconductor wafer 141, the first pre-dicing bonding member 142, and the second pre-dicing bonding member 143 are located between the first release liner 146 and the second release liner 147. The first release liner 146 prevents the first pre-dicing joining member 142 from adhering to the flat plate 911. The second release liner 147 prevents the second pre-dicing bonding member 143 from adhering to the flat plate 912.

(Modification 4)
As shown in FIG. 17, in Modification 4, the pre-press laminate 16 further includes a first release liner 166-and a second release liner 167. The second semiconductor wafer 161, the first pre-dicing bonding member 162, and the second pre-dicing bonding member 163 are located between the first release liner 166 and the second release liner 167.

(Modification 5)
In the fifth modification, the second joining members 153 and 173 do not have a property of being a sintered body when heated.

(Other modifications)
Modifications 1 to 5 and the like can be arbitrarily combined.

DESCRIPTION OF SYMBOLS 11 1st electrode mounting carrier 112 1st electrode 113 1st carrier 12 2nd electrode mounting carrier 122 2nd electrode 123 2nd carrier 15 1st chip 151 1st semiconductor element 152 1st joining member 153 2nd joining member 156 1st Post-sintering joining member 157 Second post-sintering joining member 17 Second chip 171 Second semiconductor element 172 First joining member 173 Second joining member 176 First post-sintering joining member 177 Second post-sintering joining member

Claims (6)

Fixing a first end of the semiconductor element to a first electrode disposed on the first carrier with a first joining member;
Fixing a second end of the semiconductor element to a second electrode disposed on a second carrier with a second bonding member;
Look including the step of performing sintering of the first joint member and said second joint member,
In the step of performing the sintering, at least one of the first carrier and the second carrier disappears,
A method for manufacturing a semiconductor device.   Further comprising forming a chip including the semiconductor element, the first bonding member fixed to the first end of the semiconductor element, and the second bonding member fixed to the second end of the semiconductor element. Item 2. A method for manufacturing a semiconductor device according to item 1. The step of forming the chip includes: a semiconductor wafer having both surfaces defined by a first main surface and a second main surface; a first pre-dicing bonding member fixed to the first main surface; and a semiconductor wafer fixed to the second main surface. 3. The method of manufacturing a semiconductor device according to claim 2 , further comprising the step of dicing the stacked body including the second pre-dicing bonding member. 4. The method according to claim 3 , wherein the first and second pre-dicing joining members are formed in a sheet shape.   The method of manufacturing a semiconductor device according to claim 1, wherein the first and second joining members include particles of a metal-based compound.   The method according to claim 1, wherein the semiconductor element is a thermoelectric conversion element.

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