Method for manufacturing semiconductor device having grooved surface

摘要

A technology for reducing contact resistance between a semiconductor substrate and an electrode is provided. A provided method for manufacturing a semiconductor device includes: forming an oxide film 62 on a surface 12b of a semiconductor substrate 12 by bringing the surface 12b into contact with ammonia-hydrogen peroxide water mixture; forming a groove 60 on the surface 12b by irradiating light to heat the surface 12b covered with the oxide film 62; removing the oxide film 62 to expose the surface 12b; and forming an electrode 16 on the exposed surface 12b.

主权项

1. A method for manufacturing a semiconductor device, the semiconductor device comprises:
a p-type collector region of an IGBT, the p-type collector region being exposed at a surface of a semiconductor substrate; an n-type cathode region of a diode, the n-type cathode region being exposed at the surface of the semiconductor substrate and adjacent to the p-type collector region; an n-type buffer region, the n-type buffer region being adjacent to the p-type collector region and the n-type cathode region from a deeper side, wherein an n-type impurity concentration in the n-type buffer region is lower than that in the n-type cathode region; and an n-type drift region, the n-type drift region being adjacent to the n-type buffer region from the deeper side, wherein an n-type impurity concentration in the n-type drift region is lower than that in the n-type buffer region, the method comprising: forming an oxide film on the surface of the semiconductor substrate by bringing the surface into contact with ammonia-hydrogen peroxide water mixture; forming a groove in the surface by irradiating light to heat the surface covered with the oxide film; removing the oxide film to expose the surface; and forming an electrode on the exposed surface.