Patent ID: 7405913
Filing Date: 2008-07-29
Classification: H01L

Abstract:
1. A semiconductor device, comprising: a semiconductor layer having a first conductivity type; a transistor formed in a transistor well in the semiconductor layer, the transistor well having a second conductivity type; and a vertical diode formed in a diode well in the semiconductor layer and connected in parallel with said transistor, the diode well having the second conductivity type and being spaced apart from the transistor well, wherein said diode has a resistance during breakdown operation of said diode that is smaller than a resistance of said transistor during breakdown operation of said transistor, wherein a secondary breakdown current of said diode is larger than a secondary breakdown current of said transistor, and wherein said diode has a breakdown voltage that is established at a desired value as a function of a junction depth of said diode, an impurity concentration in said well, a resistivity of said substrate, and a thickness of said substrate.