Patent ID: 11948933
Assignee: SEMICONDUCTOR COMPONENTS INDUSTRIES, LLC
Field: Semiconductors (Electrical engineering)
Classification: CPC H | IPC H

Claim 17:
18. A method of forming a semiconductor device, comprising:
providing a semiconductor substrate of a first conductivity type having a first peak dopant concentration, a top side, and a bottom side opposite to the top side;
providing a first semiconductor region of a second conductivity type opposite to the first conductivity type at a first portion of the top side, wherein:
the first semiconductor region has approximately the first peak dopant concentration and forms a first P-N junction with the semiconductor substrate; and
the first P-N junction forms a junction of a first Zener diode;

providing a second semiconductor region of the first conductivity type having a second peak dopant concentration at a second portion of the top side and laterally adjacent to the first semiconductor region;
providing a third semiconductor region of the second conductivity type overlying the first semiconductor region and a fourth semiconductor region of the first conductivity type overlying the second semiconductor region, wherein:
the third semiconductor region has a third peak dopant concentration that is less than the first peak dopant concentration; and
the fourth semiconductor region has a fourth peak dopant concentration that is less than the second peak dopant concentration;

providing a first doped region of the first conductivity type in the third semiconductor region and overlying the first semiconductor region, wherein the first doped region forms a second P-N junction with the third semiconductor region;
providing a second doped region of the second conductivity type in the fourth semiconductor region and overlying the second semiconductor region, wherein the second doped region forms a third P-N junction with the fourth semiconductor region;
providing a first conductor coupled to the first doped region and the second doped region;
providing a third doped region of the second conductivity type contiguous with the bottom side of the semiconductor substrate and having approximately the first peak dopant concentration to provide a fourth P-N junction with the semiconductor substrate, wherein the fourth P-N junction forms a junction of a second Zener diode; and
providing a second conductor contiguous with the third doped region and the bottom side of the semiconductor substrate.