Method for thinning, metalizing, and dicing a semiconductor wafer and, semiconductor device made using the method

A method of fabricating a semiconductor device, said method comprising:

• (a) forming semiconductor elements in plural element regions surrounded by elongated dicing regions on a first principal surface of a semiconductor wafer;
• (b) grinding a second principal surface, on a side of the semiconductor wafer opposite the first principal surface, in such a way that an outer peripheral portion the semiconductor wafer becomes thicker than an inner portion of the semiconductor wafer;
• (c) forming a metal film, in such a way as to avoid sections corresponding to the dicing regions, on the second principal surface that has been ground in the grinding step;
• and
• (d) cutting the semiconductor wafer from the second principal surface side along portions where the metal film is not formed on the dicing regions,
• wherein step (c) comprises:
• forming a first metal film on the second principal surface of the semiconductor wafer,
• removing sections of the first metal film coinciding with the dicing regions, and
• forming a second metal film on the first metal film remaining on the second principal surface,
• wherein the step of removing the sections of the first metal film coinciding with the dicing regions comprises:
• forming on the first metal film a resist mask having an open portion along the dicing regions, and
• etching the first metal film via the resist mask, and
• wherein the open portion is formed as a result of the resist mask being exposed to light using a glass mask that has been aligned on the basis of alignment marks formed on the first principal surface of the semiconductor wafer.

A method of fabricating a semiconductor device, said method comprising:

• (a) forming semiconductor elements in plural element regions surrounded by elongated dicing regions on a first principal surface of a semiconductor wafer;
• (b) grinding a second principal surface, on a side of the semiconductor wafer opposite the first principal surface, in such a way that an outer peripheral portion of the semiconductor wafer becomes thicker than an inner portion of the semiconductor wafer;
• (c) forming a metal film, in such a way as to avoid sections corresponding to the dicing regions, on the second principal surface that has been ground in the grinding step;
• and
• (d) cutting the semiconductor wafer from the second principal surface side along portions where the metal film is not formed on the dicing regions,
• wherein step (c) comprises:
• forming a first metal film on the second principal surface of the semiconductor wafer,
• removing sections of the first metal film coinciding with the dicing regions, and
• forming a second metal film on the first metal film remaining on the second principal surface,
• wherein the first metal film functions as a plating seed layer and the second metal film is formed by plating on the first metal film, and
• wherein the first metal film is configured by a metal whose ionization tendency is larger than the ionization tendency of the metal configuring the second metal film.