Method for fabricating semiconductor device

Abstract

A method for fabricating a semiconductor device includes: the step (a) of forming a vibrating film on a predetermined region of each of a plurality of chips included in a semiconductor wafer; the step (b) of forming, on the semiconductor wafer, an intermediate film containing a sacrifice layer located on the vibrating film of each of the chips; and the step (c) of forming a fixed film on the intermediate film. This method further includes, after the step (c), the step (d) of subjecting the semiconductor wafer 101 to blade dicing to separate the chips, and the step (e) of removing, by etching, the sacrifice layer to provide a cavity between the vibrating film and the fixed film.

1 . A method for fabricating a semiconductor device, comprising:
 the step (a) of forming a vibrating film on a predetermined region of each of a plurality of chips included in a semiconductor wafer;   the step (b) of forming, on the semiconductor wafer, an intermediate film containing a sacrifice layer located on the vibrating film of each of the chips;   the step (c) of forming a fixed film on the intermediate film;   the step (d) of subjecting the semiconductor wafer to blade dicing to separate the chips; and   the step (e) of removing, by etching each of the chips, the sacrifice layer to provide a cavity between the vibrating film and the fixed film.   
     
     
         2 . The method of  claim 1 , further comprising, before the step (d), the step of providing a protective film on the fixed film. 
     
     
         3 . The method of  claim 2 ,
 wherein in the step (e), the protective film is removed together with the sacrifice layer.   
     
     
         4 . A method for fabricating a semiconductor device, comprising:
 the step (a) of forming a vibrating film on a predetermined region of each of a plurality of chips included in a semiconductor wafer;   the step (b) of forming, on the semiconductor wafer, an intermediate film containing a sacrifice layer located on the vibrating film of each of the chips;   the step (c) of forming a fixed film on the intermediate film;   the step (d) of removing, by etching the semiconductor wafer, the sacrifice layer to provide a cavity between the vibrating film and the fixed film; and   the step (e) of subjecting the semiconductor wafer to laser dicing to separate the chips.   
     
     
         5 . The method of  claim 4 ,
 wherein in the step (e), a surface protective tape is stuck onto the surface of the semiconductor wafer formed with the fixed film, and then the laser dicing is performed from the other-surface side of the semiconductor wafer.   
     
     
         6 . The method of  claim 4 ,
 wherein in the step (e), a dicing tape is stuck onto the surface of the semiconductor wafer opposite to the surface formed with the fixed film, and then the laser dicing is performed from the surface side thereof formed with the fixed film.   
     
     
         7 . The method of  claim 4 , further comprising, after the step (d) and before the step (e), the step of sticking a surface protective tape onto the surface of the semiconductor wafer formed with the fixed film, and then grinding the other surface of the semiconductor wafer,
 wherein in the step (e), the laser dicing is performed from the other-surface side of the semiconductor wafer.   
     
     
         8 . The method of  claim 4 ,
 wherein the step (e) comprises:   the substep of radiating the surrounding of each of the chips with a laser to form an altered layer surrounding each said chip; and   the substep of applying a force to the semiconductor wafer to separate the chips along the altered layer.   
     
     
         9 . A method for fabricating a semiconductor device, comprising:
 the step (a) of forming a vibrating film on a predetermined region of each of a plurality of chips included in a semiconductor wafer;   the step (b) of forming, on the semiconductor wafer, an intermediate film containing a sacrifice layer located on the vibrating film of each of the chips;   the step (c) of forming a fixed film on the intermediate film;   the step (d) of removing, by etching the semiconductor wafer, the sacrifice layer to provide a cavity between the vibrating film and the fixed film; and   the step (e) of providing, after the step (d), a protective film on the fixed film, and subjecting the resulting semiconductor wafer to blade dicing to separate the chips.   
     
     
         10 . The method of  claim 9 , further comprising, after the step (e), the step of removing the protective film with each of the chips held on a chip holder. 
     
     
         11 . The method of  claim 9 ,
 wherein in the step (e), the blade dicing is performed in the state in which a dicing tape is stuck onto the surface of the semiconductor wafer opposite to the surface formed with the fixed film, and   the method further comprises, after the step (e), the step of removing the protective film from each of the chips which are held stuck onto the dicing tape.   
     
     
         12 . A method for fabricating a semiconductor device, comprising:
 the step (a) of forming a vibrating film on a predetermined region of each of a plurality of chips included in a semiconductor wafer;   the step (b) of forming, on the semiconductor wafer, an intermediate film containing a sacrifice layer located on the vibrating film of each of the chips;   the step (c) of forming a fixed film on the intermediate film;   the step (d) of forming, from the fixed film side, a groove in portions of the fixed film, the intermediate film, and the semiconductor wafer, the groove surrounding each of the chips;   the step (e) of removing, by etching the semiconductor wafer formed with the groove, the sacrifice layer to provide a cavity between the vibrating film and the fixed film; and   the step (f) of grinding, after the step (e), the surface of the semiconductor wafer opposite to the surface formed with the groove until the ground surface reaches the groove, thereby separating the chips.   
     
     
         13 . The method of  claim 12 ,
 wherein in the step (d), the groove is formed a predetermined distance away from the vibrating film of each of the chips.