Method of forming superjunction high voltage devices using wafer bonding

摘要

A method of forming a superjunction device includes providing a semiconductor layer having first and second opposing main surfaces and a first doping concentration of a dopant of a first conductivity type, forming at least one device proximate the first main surface, forming at least one trench adjacent to the device and extending into the semiconductor layer from the first main surface, doping at least a portion of a sidewall of the trench with a dopant of a second, different conductivity type to form a first region in the semiconductor layer adjacent to the sidewall and extending at least partially between the first and second main surfaces, providing a substrate with a first dielectric layer arranged thereon, bonding the first dielectric layer to the first main surface to cover the trench and at least a portion of the device, and removing the substrate.

主权项

1. A method of forming a superjunction device, the method comprising:
providing a semiconductor layer having first and second opposing main surfaces and a first doping concentration of a dopant of a first conductivity type; forming at least one trench extending at least partially into the semiconductor layer from the first main surface thereof; doping at least a portion of a sidewall of the at least one trench with the dopant of the first conductivity type to form a first region in the semiconductor layer extending at least partially between the first and second main surfaces of the semiconductor layer, the first region having a second doping concentration; doping at least a portion of the sidewall of the at least one trench with a dopant of a second conductivity type different from the first conductivity type to form a second region in the semiconductor layer between the sidewall of the at least one trench and the first region and extending at least partially between the first and second main surfaces of the semiconductor layer, the second region having a third doping concentration; providing a substrate with a first dielectric layer arranged thereon; bonding the first dielectric layer of the substrate to the first main surface of the semiconductor layer to cover the at least one trench and at least a portion of the first main surface; removing the substrate; removing at least a portion of the first dielectric layer from the first main surface of the semiconductor layer to form at least one active region; and forming a device in the at least one active region.