Hybrid polycrystalline and amorphous silicon structures on a shared substrate

US6504175B1 · kind B1 · utility

Assignee

• Xerox Corporation · US

Inventors

• Ping Mei · Palo Alto, US
• Rene A. Lujan · Sunnyvale, US

Key dates

• Filing date: Apr 28, 1998
• Grant date: Jan 7, 2003
• Expiry date: Apr 28, 2018

Classification

• Technology area (CPC H): Electricity
• CPC primary: H10D86/431

Abstract

Amorphous and polycrystalline silicon (hybrid) devices are formed close to one another employing laser crystallization and back side lithography processes. A mask (e.g., TiW) is used to protect the amorphous silicon device during laser crystallization. A patterned nitride layer is used to protect the amorphous silicon device during rehydrogenation of the polycrystalline silicon. An absorption film (e.g., amorphous silicon) is used to compensate for the different transparencies of amorphous and polycrystalline silicon during the back side lithography. Device spacing of between 2 and 50 micrometers may be obtained, while using materials and process steps otherwise compatible with existing hybrid device formation processes.