Method and apparatus improving gate oxide reliability by controlling accumulated charge

USRE48965E1 · kind E1 · reissue

Assignee

• pSemi Corporation · US

Inventors

• Michael A. Stuber · Carlsbad, US
• Christopher N. Brindle · Poway, US
• Dylan J. Kelly · San Diego, US
• Clint L. Kemerling · Escondido, US
• George Imthurn · San Diego, US
• Robert B. Welstand · San Diego, US
• Mark L. Burgener · San Diego, US
• Alexander Dribinsky · Naperville, US
• Tae Youn Kim · Daejeon, KR

Key dates

• Filing date: Dec 11, 2019
• Grant date: Mar 8, 2022
• Expiry date: Dec 11, 2039

Classification

• Technology area (CPC —): General

Abstract

A method and apparatus are disclosed for use in improving the gate oxide reliability of semiconductor-on-insulator (SOI) metal-oxide-silicon field effect transistor (MOSFET) devices using accumulated charge control (ACC) techniques. The method and apparatus are adapted to remove, reduce, or otherwise control accumulated charge in SOI MOSFETs, thereby yielding improvements in FET performance characteristics. In one embodiment, a circuit comprises a MOSFET, operating in an accumulated charge regime, and means for controlling the accumulated charge, operatively coupled to the SOI MOSFET. A first determination is made of the effects of an uncontrolled accumulated charge on time dependent dielectric breakdown (TDDB) of the gate oxide of the SOI MOSFET. A second determination is made of the effects of a controlled accumulated charge on TDDB of the gate oxide of the SOI MOSFET. The SOI MOSFET is adapted to have a selected average time-to-breakdown, responsive to the first and second determinations, and the circuit is operated using techniques for accumulated charge control operatively coupled to the SOI MOSFET. In one embodiment, the accumulated charge control techniques include using an …