Semiconductor device, method of manufacturing the device, and liquid crystal display

Abstract

In order to shield the light incident from the chip side surface or chip rear surface of a semiconductor chip that forms an LCD driver, a light-shielding film is formed over the chip side surface and chip rear surface of the semiconductor chip itself, not using a light-shielding tape that is a component separate from the semiconductor chip. Accordingly, the light-shielding tape as a separate component is not used, and hence the trouble that the light-shielding tape may protrude from the surface of a glass substrate whose thickness has been made small can be solved. As a result, the thinning of a liquid crystal display, and the subsequent thinning of the mobile phone in which the liquid crystal display is mounted can be promoted.

What is claimed is: 
     
         1 . A method of manufacturing a semiconductor device to be mounted over a substrate arranged in a case having a light source, the method comprising the steps of:
 (a) providing a semiconductor wafer having a main surface, a plurality of chip formation regions provided over the main surface, a scribe region provided between the chip formation regions adjacent to each other, and a rear surface opposite to the main surface;   (b) after the (a) step, removing a part of the scribe region;   (c) after the (b) step, dividing the semiconductor wafer into a plurality of semiconductor chips by grinding the rear surface of the semiconductor wafer in such a state that the main surface of the semiconductor wafer is adhered to a back grinding tape, the semiconductor chips each having a chip main surface, a chip rear surface opposite to the chip main surface, and a chip side surface between the chip main surface and the chip rear surface; and   (d) after the (c) step, forming a light-shielding film over both the chip rear surface and the chip side surface of each of the semiconductor chips.   
     
     
         2 . The method of manufacturing a semiconductor device according to  claim 1  comprising:
 (e) after the (c) step and before the (d) step, etching both the chip rear surface and the chip side surface of each of the semiconductor chips. 
 
     
     
         3 . The method of manufacturing a semiconductor device according to  claim 2 ,
 wherein in the (e) step, the chip rear surface and the chip side surface of each of the semiconductor chips are subjected to plasma etching in such a state that the chip main surface of each of the semiconductor chips is adhered to the back grinding tape.   
     
     
         4 . The method of manufacturing a semiconductor device according to  claim 2 ,
 wherein in the (e) step, the chip rear surface and the chip side surface of each of the semiconductor chips are wet-etched in such a state that the chip main surface of each of the semiconductor chips is adhered to the back grinding tape.   
     
     
         5 . The method of manufacturing a semiconductor device according to  claim 1 ,
 wherein in the (d) step, the back grinding tape is extended, and the light-shielding film is formed over both the chip rear surface and the chip side surface of each of the semiconductor chips in such a state that the back grinding tape is extended.   
     
     
         6 . The method of manufacturing a semiconductor device according to  claim 1 ,
 wherein in the (d) step, the light-shielding film is formed over both the chip rear surface and the chip side surface of each of the semiconductor chips by using any one of a sputtering process, deposition process, and CVD process.   
     
     
         7 . The method of manufacturing a semiconductor device according to  claim 1 ,
 wherein the light-shielding film is formed by a metal film or an insulating film.   
     
     
         8 . The method of manufacturing a semiconductor device according to  claim 1 ,
 wherein in the (b) step, the rear surface of the semiconductor wafer is adhered to a dicing tape, and a blade is driven on the main surface side of the semiconductor wafer in such a state that the rear surface of the semiconductor wafer is adhered to the dicing tape.   
     
     
         9 . The method of manufacturing a semiconductor device according to  claim 1  comprising:
 (f) after the (d) step, adhering a pickup tape to the chip rear surface of each of the semiconductor chips; 
 (g) after the (f) step, extending the pickup tape; and 
 (h) after the (g) step, picking up each of the semiconductor chips. 
 
     
     
         10 . A method of manufacturing a semiconductor device to be mounted over a substrate arranged in a case having a light source, the method comprising the steps of:
 (a) providing a semiconductor wafer having a main surface, a plurality of chip formation regions provided over the main surface, a scribe region provided between the chip formation regions adjacent to each other, and a rear surface opposite to the main surface;   (b) after the (a) step, obtaining a plurality of semiconductor chips by cutting the scribe region along the scribe region in the semiconductor wafer; and   (c) after the (b) step, forming a light-shielding film over each of a chip rear surface and a chip side surface of each of the semiconductor chips.   
     
     
         11 . The method of manufacturing a semiconductor device according to  claim 10  comprising:
 (d) after the (b) step and before the (c) step, etching both the chip rear surface and the chip side surface of each of the semiconductor chips. 
 
     
     
         12 . The method of manufacturing a semiconductor device according to  claim 11 ,
 wherein in the (d) step, the chip rear surface and the chip side surface of each of the semiconductor chips are subjected to plasma etching in such a state that the chip main surface of each of the semiconductor chips is adhered to a tape.   
     
     
         13 . The method of manufacturing a semiconductor device according to  claim 11 ,
 wherein in the (d) step, the chip rear surface and the chip side surface of each of the semiconductor chips are wet-etched in such a state that the chip main surface of each of the semiconductor chips is adhered to a tape.   
     
     
         14 . The method of manufacturing a semiconductor device according to  claim 10 ,
 wherein in the (c) step, a tape adhered to the chip main surface of each of the semiconductor chips is extended, and the light-shielding film is formed over both the chip rear surface and the chip side surface of each of the semiconductor chips in such a state that the tape is extended.   
     
     
         15 . The method of manufacturing a semiconductor device according to  claim 10 ,
 wherein in the (c) step, the light-shielding film is formed over both the chip rear surface and the chip side surface of each of the semiconductor chips by using any one of a sputtering process, deposition process, and CVD process.   
     
     
         16 . The method of manufacturing a semiconductor device according to  claim 10  comprising:
 (e) after the (a) step and before (b) step, coating a resist film over the rear surface of the semiconductor wafer to form the resist film in which part of each of the scribe regions in the semiconductor wafer is at least opened, by patterning the coated resist film; and 
 (f) after the (e) step and before the (b) step, removing part of an exposed area in the semiconductor wafer by performing etching in which the patterned resist film is used as a mask. 
 
     
     
         17 . The method of manufacturing a semiconductor device according to  claim 10 ,
 wherein the (b) step includes:   (b1) forming, from the rear surface side of the semiconductor wafer, a cut in the semiconductor wafer by using a first blade having a first thickness, the cut being made to the middle of the thickness of the semiconductor wafer; and   (b2) after the (b1) step, cutting, from the rear surface side of the semiconductor wafer, the semiconductor wafer by using a second blade having a second thickness smaller than the first thickness.