Semiconductor device and method for manufacturing the same
A semiconductor device includes a semiconductor substrate, an end region, and an active region. The end region is located above the semiconductor substrate, has a frame shape, and has been brought into contact with a blade in a scribing process. The active region is surrounded by the end region and is configured to serve as a path of a main current. The end region has a stress relaxation film on an outermost surface of the end region.
1 . A manufacturing method of a semiconductor device, comprising:
preparing a semiconductor wafer having a first surface and a second surface opposite to each other;
forming a plurality of active regions on the semiconductor wafer, each of the plurality of active regions configured to serve as a path of a main current;
forming a dicing region having a lattice shape that divides the plurality of active regions;
forming a vertical crack to the first surface of the semiconductor wafer in the dicing region using a blade; and
dividing the semiconductor wafer into a plurality of pieces with the vertical crack as a starting point by pressing the semiconductor wafer from a direction close to the second surface after forming the vertical crack, wherein
the forming the dicing region includes forming the dicing region to have a laminated structure in which a stress relaxation film, an insulating film, and the semiconductor wafer are laminated in order from an outermost surface of the dicing region or a laminated structure in which a stress relaxation film that is made of an insulating material and the semiconductor wafer are laminated in order from the outermost surface of the dicing region,
the forming the vertical crack includes forming the vertical crack to the first surface of the semiconductor wafer from a direction close to the stress relaxation film, and
the dividing the semiconductor wafer includes cleaving the semiconductor wafer with the vertical crack as the starting point.
2 . The manufacturing method according to claim 1 , wherein
the forming the dicing region includes forming the insulating film made of SiO 2 .
3 . The manufacturing method according to claim 1 , wherein
the forming the dicing region includes forming the stress relaxation film to be thicker than the insulating film.
4 . The manufacturing method according to claim 1 , wherein
the preparing the semiconductor wafer includes preparing the semiconductor wafer made of SiC.
5 . The manufacturing method according to claim 1 , wherein
the forming the dicing region includes forming the stress relaxation film made of an aluminum alloy material or polyimide having a Vickers hardness of less than 100 HV.
6 . The manufacturing method according to claim 1 , wherein
the cleaving the semiconductor wafer includes
attaching a protective film to the first surface of the semiconductor wafer,
attaching a fixing tape to the second surface of the semiconductor wafer,
placing the semiconductor wafer on a pedestal, and
pressing a breaking plate against the second surface of the semiconductor wafer.
7 . The manufacturing method according to claim 1 , further comprising
forming a rear surface electrode having a conductive material on the second surface of the semiconductor wafer.
8 . The manufacturing method according to claim 7 , further comprising
subsequent to the forming of the rear surface electrode, subjecting the semiconductor wafer to a heat treatment in an inert gas atmosphere.
9 . The manufacturing method according to claim 1 , wherein
the forming the vertical crack includes pressing the insulating film with the blade through the stress relaxation film.
10 . The manufacturing method according to claim 1 , wherein
the forming the dicing region includes forming the insulating film by chemical vapor deposition.