Claims
- 1. A method for providing an ESD transistor in a flash memory chip, the flash memory chip having a core area and a periphery area, comprising the steps of(a) forming select gate transistors that have a stacked gate structure in the core area; (b) while forming the transistors in the core area, forming an ESD transistor in the periphery area where ESD circuits are desired by providing a select gate transistor that includes a gate, a floating gate, and a medium doped junction; and (c) forming a source and drain for the ESD transistor by i) performing a lightly doped drain (LDD) mask and etch, ii) performing a LDD spacer deposition and LDD spacer etch, and iii) performing a N+ implant mask and a N+ implant.
- 2. The method of claim 1 wherein step (a) i) further includes the step of forming the gate with type-2 polysilicon.
- 3. The method of claim 2 wherein step (a) i) further includes the step of forming the floating gate with type-1 polysilicon.
- 4. A flash memory chip, comprising:a core area comprising stacked gate transistors; and a periphery area having at least one ESD transistor, the ESD transistor formed from a stacked gate transistor including, a gate, a floating gate, a medium doped junction, and a source and drain, wherein the source and drain are formed by performing a lightly doped drain (LDD) mask and etch, a LDD spacer deposition and LDD spacer etch, and a N+ implant mask and a N+ implant.
- 5. An ESD transistor as in claim 4 wherein the gate is formed with type-2 polysilicon.
- 6. An ESD transistor as in claim 5 wherein the floating gate is formed with type-1 polysilicon.
- 7. An ESD transistor as in claim 6 wherein the gate, the floating gate, and medium doped junction form a select gate transistor in a memory array.
Parent Case Info
This application claims the benefit of Provisional application Ser. No. 60/169,700, filed Dec. 6, 1999.
US Referenced Citations (1)
Number |
Name |
Date |
Kind |
4982250 |
Manos et al. |
Jan 1991 |
A |
Provisional Applications (1)
|
Number |
Date |
Country |
|
60/169700 |
Dec 1999 |
US |