METHOD FOR MANUFACTURING SEMICONDUCTOR DEVICE CAPABLE OF HOMOGENIZING THRESHOLD VOLTAGES OF TRANSISTORS

摘要

PURPOSE: A method for manufacturing a semiconductor device is provided to improve device characteristics and reliability by preventing variation of threshold voltages of transistors. CONSTITUTION: A gate(22) is formed on a semiconductor substrate. A buffer oxide layer(23) is formed on the substrate. The substrate is thermally processed. Phosphorous(24) is doped in a phosphorous atmosphere on the buffer oxide layer. A gate spacer nitride layer(25) is deposited on a front portion of the surface having the phosphorous-doped buffer oxide layer. A gate spacer(26) is formed on both sidewalls of the gate by blanket-etching the gate spacer nitride layer and the buffer oxide layer. A cell spacer nitride layer(28) and an interlayer dielectric(29) are sequentially deposited on the substrate. A CMP(Chemical Mechanical Polishing) is performed on the interlayer dielectric and the cell spacer nitride layer to expose the gate.