Patent ID: 6180968
Filing Date: 2001-01-30
Classification: H01L

Abstract:
A compound semiconductor device comprising a semiconductor multilayered structure, said semiconductor multilayered structure comprising;a first recess etch-stop layer formed on a conductive layer of a compound semiconductor said first recess etch-stop layer comprising a first etch-stop layer opening;a first semiconductor layer formed on said first recess etch-stop layer said first semiconductor layer comprising a first semiconductor layer opening with sloped sidewalls;a second recess etch-stop layer formed on said first semiconductor layer said second recess etch-stop layer comprising a second etch-stop layer opening; anda second semiconductor layer formed on said second recess etch-stop layer said second semiconductor layer comprising a second semiconductor layer opening with sloped sidewalls;wherein said second semiconductor layer is doped more heavily than said first semiconductor layer and a top portion of said second semiconductor layer opening is wider than a lower portion of said second semiconductor layer opening and said lower portion of said second semiconductor layer opening is wider than a top portion of said first semiconductor layer opening and said top portion of said first semiconductor layer opening is wider than a lower portion of said first semiconductor layer opening.