Method for forming high resistance resistor with integrated high voltage device process

US6624079B2 · kind B2 · utility

Assignee

• UNITED MICROELECTRONICS CORP. · TW

Inventors

• Yuan-Li Tsai · Taipei, TW
• Marcus Yang · Hsinchu, TW
• Ralph Chen · Bothell, US
• Heng-Chun Kao · Taipei, TW
• Ching-Chun Hwang · Taichung, TW

Key dates

• Filing date: Aug 20, 2001
• Grant date: Sep 23, 2003
• Expiry date: Sep 21, 2021

Classification

• Technology area (CPC H): Electricity
• CPC primary: H10D84/212

Abstract

The method for forming high voltage device combined with a mixed mode process use an un-doped polysilicon layer instead of the conventional polysilicon layer. In the high resistance area, the ion implant is not used until the source region and the drain region are formed. A resistor is formed by etching oxide-nitride-oxide layer and performing ion implant process by using BF2 radical to the un-doped polysilicon layer to control the resistance. Then multitudes of contact are formed, wherein the high dosage of BF2 implant would reduce resistance between contacts and resistor.