Semiconductor device including a circuit for transmitting a signal

Abstract

Reliability of a semiconductor device is improved. The semiconductor device includes a wiring substrate, a semiconductor chip and a capacitor mounted on the upper surface of the wiring substrate, and a lid formed of a metallic plate covering the semiconductor chip and the wire in substrate. The semiconductor chip is bonded to the lid via a conductive adhesive layer, and the capacitor, which is thicker than the thickness of the semiconductor chip, is disposed in the cut off portion provided in the lid, and is exposed from the lid.

What is claimed is: 
     
         1 . A semiconductor device comprising:
 a wiring substrate having a first main surface and a second main surface opposite the first main surface, the first main surface having a central portion and a peripheral portion surrounding the central portion in plan view;   a semiconductor chip having a front surface and a rear surface opposite the front surface, the semiconductor chip being mounted on the central portion of the first main surface of the wiring substrate;   a first capacitor mounted on the peripheral portion of the first main surface of the wiring substrate; and   a lid disposed over the first main surface of the wiring substrate such that the lid covers the semiconductor chip, the lid having a heat radiation portion and a flange portion surrounding the heat radiating portion,   wherein in plan view, the first main surface of the wiring substrate has a rectangular shape comprised of:
 a first side extending in a first direction; 
 a second side opposite the first side and extending in the first direction; 
 a third side extending in a second direction perpendicular to the first direction; and 
 a fourth side opposite the third side and extending in the second direction, 
   wherein in plan view, the peripheral portion of the first main surface of the wiring substrate has:
 a first corner portion including a first corner defined by the first side and the third side; 
 a second corner portion including a second corner defined by the third side and the second side; 
 a third corner portion including a third corner defined by the second side and the fourth side; 
 a fourth corner portion including a fourth corner defined by the fourth side and the first side; 
 a first middle portion located between the first corner portion and the second corner portion, in the second direction; 
 a second middle portion located between the second corner portion and the third corner portion, in the first direction; 
 a third middle portion located between the third corner portion and the fourth corner portion, in the second direction; and 
 a fourth middle portion located between the fourth corner portion and the first corner portion, in the first direction, 
   wherein the first capacitor is mounted on the first middle portion of the peripheral portion of the first main surface of the wiring substrate, and   wherein the flange portion of the lid is bonded to the wiring substrate via a first adhesive layer at each corner portion of the peripheral portion of the first main surface of the wiring substrate such that the flange portion of the lid is not bonded to the wiring substrate at each middle portion of the peripheral portion of the first main surface of the wiring substrate.   
     
     
         2 . The semiconductor device according to  claim 1 , further comprising a second capacitor mounted on the third middle portion of the peripheral portion of the first main surface of the wiring substrate. 
     
     
         3 . The semiconductor device according to  claim 2 ,
 wherein the semiconductor chip is mounted on the central portion of the first main surface of the wiring substrate such that the front surface of the semiconductor chip faces the first main surface of the wiring substrate,   wherein the heat radiation portion of the lid is bonded to the rear surface of the semiconductor chip via a second adhesive layer,   wherein a thickness of the semiconductor chip is thinner than a thickness of each of the first through second capacitors,   wherein in cross-sectional view, a mounting height of each of the first through second capacitors from the first main surface of the wiring substrate is higher than a mounting height of the semiconductor chip from the first main surface of the wiring substrate,   wherein in plan view, the lid has:
 a first notched portion concaved from a peripheral edge of the lid toward the heat radiation portion in plan view; and 
 a second notched portion concaved from the peripheral edge of the lid toward the heat radiation portion in plan view, and 
   wherein the lid is disposed over the first main surface of the wiring substrate such that the first capacitor is exposed from the lid at the first notched portion and such that the second capacitor is exposed from the lid at the second notched portion.   
     
     
         4 . The semiconductor device according to  claim 3 , further comprising:
 a third capacitor mounted on the second middle portion of the peripheral portion of the first main surface of the wiring substrate; and   a fourth capacitor mounted on the fourth middle portion of the peripheral portion of the first main surface of the wiring substrate.   
     
     
         5 . The semiconductor device according to  claim 4 ,
 wherein the thickness of the semiconductor chip is thinner than a thickness of each of the third through fourth capacitors,   wherein in cross-sectional view, a mounting height of each of the third through fourth capacitors from the first main surface of the wiring substrate is higher than the mounting height of the semiconductor chip from the first main surface of the wiring substrate,   wherein in plan view, the lid has:
 a third notched portion concaved from the peripheral edge of the lid toward the heat radiation portion in plan view; and 
 a fourth notched portion concaved from the peripheral edge of the lid toward the heat radiation portion in plan view, and 
   wherein the lid is disposed over the first main surface of the wiring substrate such that the third capacitor is exposed from the lid at the third notched portion and such that the fourth capacitor is exposed from the lid at the fourth notched portion.   
     
     
         6 . The semiconductor device according to  claim 5 ,
 wherein each of the first capacitor and the second capacitor is a DC (Direct Current) cutting capacitor, and   wherein each of the third capacitor and the fourth capacitor is a bypass capacitor.   
     
     
         7 . The semiconductor device according to  claim 6 ,
 wherein each of the first adhesive layer and the second adhesive layer is made of a conductive material, and   wherein the flange portion of the lid is connected to an electrode of the wiring substrate via the first adhesive layer, a reference potential being to be applied to the electrode.   
     
     
         8 . The semiconductor device according to  claim 4 ,
 wherein the thickness of the semiconductor chip is thinner than a thickness of each of the third through fourth capacitors,   wherein in cross-sectional view, a mounting height of each of the third through fourth capacitors from the first main surface of the wiring substrate is higher than the mounting height of the semiconductor chip from the first main surface of the wiring substrate,   wherein in plan view, the lid has a first opening portion and a second opening portion, and   wherein the lid is disposed over the first main surface of the wiring substrate such that the third capacitor is exposed from the lid at the first opening portion and such that the fourth capacitor is exposed from the lid at the second opening portion.   
     
     
         9 . The semiconductor device according to  claim 8 ,
 wherein each of the first capacitor and the second capacitor is a DC (Direct Current) cutting capacitor, and   wherein each of the third capacitor and the fourth capacitor is a bypass capacitor.   
     
     
         10 . The semiconductor device according to  claim 9 ,
 wherein each of the first adhesive layer and the second adhesive layer is made of a conductive material, and   wherein the flange portion of the lid is connected to an electrode of the wiring substrate via the first adhesive layer, a reference potential being to be applied to the electrode.   
     
     
         11 . The semiconductor device according to  claim 1 ,
 wherein the semiconductor chip is mounted on the central portion of the first main surface of the wiring substrate such that the front surface of the semiconductor chip faces the first main surface of the wiring substrate,   wherein the heat radiation portion of the lid is bonded to the rear surface of the semiconductor chip via a second adhesive layer,   wherein a thickness of the semiconductor chip is thinner than a thickness of the first capacitor,   wherein in cross-sectional view, a mounting height of the first capacitor from the first main surface of the wiring substrate is higher than a mounting height of the semiconductor chip from the first main surface of the wiring substrate,   wherein in plan view, the lid has a first notched portion concaved from a peripheral edge of the lid toward the heat radiation portion in plan view, and   wherein the lid is disposed over the first main surface of the wiring substrate such that the first capacitor is exposed from the lid at the first notched portion.   
     
     
         12 . The semiconductor device according to  claim 1 , further comprising:
 a fifth capacitor mounted on the central portion of the first main surface of the wiring substrate,   wherein a thickness of the semiconductor chip is thinner than a thickness of the fifth capacitor,   wherein in cross-sectional view, a mounting height of the fifth capacitor from the first main surface of the wiring substrate is higher than a mounting height of the semiconductor chip from the first main surface of the wiring substrate,   wherein in plan view, the lid has a first opening portion provided in the heat radiation portion, and   wherein the lid is disposed over the first main surface of the wiring substrate such that the fifth capacitor is exposed from the lid at the first opening portion.   
     
     
         13 . The semiconductor device according to  claim 12 ,
 wherein the first capacitor is a DC (Direct Current) cutting capacitor, and   wherein the fifth capacitor is a bypass capacitor.   
     
     
         14 . The semiconductor device according to  claim 13 ,
 wherein the first adhesive layer is made of a conductive material, and   wherein the flange portion of the lid is connected to an electrode of the wiring substrate via the first adhesive layer, a reference potential being to be applied to the electrode.   
     
     
         15 . The semiconductor device according to  claim 1 ,
 wherein the first adhesive layer is made of a conductive material, and   wherein the flange portion of the lid is connected to an electrode of the wiring substrate via the first adhesive layer, a reference potential being to be applied to the electrode.