| 摘要 |
PURPOSE: A method for fabricating an SRAM cell is provided to reduce largely the area of the SRAM cell by using a pull-up device of the SRAM cell as a P-channel TFT instead of a PMOS transistor. CONSTITUTION: A gate oxide layer(2) and a gate are formed on a semiconductor substrate(1) including an isolation layer and a well. An LDD(Lightly Doped Drain) region(4) is formed at the outside of the gate by an LDD ion implantation process. A spacer(5) is formed at both sides of the gate. A source/drain region(6) is formed on the semiconductor substrate of the outside of the spacer by performing an impurity ion implantation process. An insulating layer(7) is formed on the resultant. The insulating layer is planarized by performing a CMP(Chemical Mechanical Polishing) process. The insulating layer is removed from the gate by performing an etch-back process. A gate insulating layer(8) of a P-channel TFT is deposited thereon and an annealing process is performed. A polysilicon layer(9) is deposited and crystallized on the resultant. A junction region of the P-channel TFT is formed by a doping process.
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