J. C. Patents
Method of fabricating gate
A method of fabricating a gate. A gate dielectric layer is formed, and a lower portion of a floating gate is formed encompassed by a first dielectric layer. Second dielectric layers with different etching rates are formed to cover the upper portion of the floating gate and the first dielectric layer. Using an etching mask, an opening is formed within the second dielectric layer to expose the floating gate and a portion of the second dielectric layers by performing an anisotropic etching process. Using the same etching mask, the second dielectric layers exposed within the opening is further etched by performing an isotropic etching process. Due to the different etching rates, a dielectric layer with an uneven and enlarged surface is formed. A conformal conductive layer is formed on the exposed lower portion of the floating gate and the exposed second dielectric layers as an upper portion of the floating gate. A conformal third dielectric layer is formed on the conformal conductive layer, followed by forming a control gate on the third dielectric layer.
Macronix International Co., Ltd.
H H
H01L H01L
inventional inventional
Ching-Yu
Chang