P-type control gate in non-volatile storage and methods for forming same

US8546214B2 · kind B2 · utility

Assignee

• Sandisk Technologies, Inc. · US

Inventors

• Takashi Orimoto · Sunnyvale, US
• Atsushi Suyama · Osaka, JP
• Ming Tian · Nanhu, CN
• Henry Chin · Fremont, US
• Henry Chien · San Jose, US
• Vinod R. Purayath · Santa Clara, US
• Dana Lee · Saratoga, US

Key dates

• Filing date: Sep 21, 2010
• Grant date: Oct 1, 2013
• Expiry date: Sep 18, 2031

Classification

• Technology area (CPC H): Electricity
• CPC primary: H10D64/035

Abstract

Non-voltage storage and techniques for fabricating non-volatile storage are disclosed. In some embodiments, at least a portion of the control gates of non-volatile storage elements are formed from p-type polysilicon. In one embodiment, a lower portion of the control gate is p-type polysilicon. The upper portion of the control gate could be p-type polysilicon, n-type polysilicon, metal, metal nitride, etc. P-type polysilicon in the control gate may not deplete even at high Vpgm. Therefore, a number of problems that could occur if the control gate depleted are mitigated. For example, a memory cell having a control gate that is at least partially p-type polysilicon might be programmed with a lower Vpgm than a memory cell formed from n-type polysilicon.