Method of manufacturing solid-state imaging device

Abstract

A solid-state imaging device with an improved heat release-ability for releasing a heat generated in the amplifier unit of the solid-state image sensing element. The solid-state imaging device 10 of the present invention includes an elongated substrate (molded case 18 ), a metallic layer 16 exposed in a surface of the molded case 18 and extending along an elongating direction of the molded case 18 , and an elongated solid-state image sensing element 20 mounted on the metallic layer 16 , in which a thickness in a region of a metallic layer 16 right under an amplifier unit of the solid-state image sensing element 20 is larger than thicknesses in other regions of the metallic layer 16.

1 . A method of manufacturing a solid-state imaging device which comprises a first metallic layer, a solid-state image sensing element which includes an amplifier unit therein mounted on an upper surface the first metallic layer, and a second metallic layer adhered to a lower surface of the first metallic layer, the method comprising:
 plating at least a region of the lower surface of the first metallic layer with one metal selected from a metal group consisting of gold and tin so that the region is located right under the amplifier unit of the solid-state image sensing element;   plating a top surface of the second metallic layer with another metal selected from the metal group consisting of gold and tin; and   adhering the top surface of the second metallic layer plated with the other metal to the region of the lower surface of the first metallic layer plated with the one metal via heating and compressing to form a gold-tin alloy made from the metal group consisting of gold and tin.   
     
     
         2 . The method as set forth in  claim 1 , wherein the first metallic layer is plated with gold and the second metallic layer is plated with tin. 
     
     
         3 . The method as set forth in  claim 1 , wherein the first metallic layer is plated with tin and the second metallic layer is plated with gold. 
     
     
         4 . The method as set forth in  claim 1 , wherein the first metallic layer contains at least one metal selected from a group consisting of copper, aluminum and an alloy thereof. 
     
     
         5 . The method as set forth in  claim 1 , wherein the second metallic layer contains at least one metal selected from a group consisting of copper, aluminum and an alloy thereof. 
     
     
         6 . The method as set forth in  claim 1 , wherein a thickness of the second metallic layer is equal to or larger than 1 mm. 
     
     
         7 . The method as set forth in  claim 1 , wherein the first metallic layer includes a depressed portion at a region except the region right under the amplifier unit, at least one protruding portion is formed on a top surface of the depressed portion of the first metallic layer, the solid-state image sensing element is partially mounted on the first metallic layer in the region right under the amplifier unit and is also partially mounted on the protruding portion, so that the solid-state image sensing element is substantially horizontally maintained.