METHOD OF FORMING A FLOATING GATE IN A SEMICONDUCTOR DEVICE

摘要

A method for forming a floating gate in a semiconductor device is provided to guarantee capacitance of an ONO layer and increase a coupling ratio by controlling generation of seams or voids in the upper part of a floating gate. A tunnel oxide layer(104) and an undoped first polysilicon layer(106) are formed on a semiconductor substrate(100) having an isolation layer(102) with a slope nipple. An annealing process is performed on the surface of the undoped first polysilicon layer. A doped second polysilicon layer is formed on the undoped first polysilicon layer. The undoped first polysilicon layer is deposited by using SiH4 or Si2H6 gas.