Metallized sloping step for a metal clad ridge waveguide semiconductor laser is produced by selectively etching a semiconductor substrate surface exposed by a partial metallization of finer grain structure than gold

摘要

Metallized sloping step production involves selectively etching a semiconductor substrate surface (13) exposed by a partial metallization (2) of finer grain structure than gold. Production of a sloping step (102, 103) and an adjacent metallization (2) on a semiconductor substrate surface (13) comprises: (a) partially covering the surface (13) with a metallization (2) which is finer than gold and which forms a metal-semiconductor junction contact (212), the metallization edge (202, 203) defining the contour of the step flanks (102, 103) to be produced; and (b) etching the exposed surface (13) in the vertical direction using an etchant which is more selective for the semiconductor material than the metallization. Independent claims are also included for the following: (i) a semiconductor substrate with a sloping step (102, 103) and an adjacent metallization (2), produced by the above process; and (ii) a MCRW (metal clad ridge waveguide) semiconductor laser on the above substrate having a metallized ridge (100).