Polysilicon layer and method of forming the same
AssigneeUnited Microelectronics Corp.
InventorsChien-Liang Lin, Yun-Ren Wang, Ying-Wei Yen, Wen-Yi Teng, Chan-Lon Yang
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Abstract
The method of forming a polysilicon layer is provided. A first polysilicon layer with a first grain size is formed on a substrate. A second polysilicon layer with a second grain size is formed on the first polysilicon layer. The first grain size is smaller than the second grain size. The first polysilicon layer with a smaller grain size can serve as a base for the following deposition, so that the second polysilicon layer formed thereon has a flatter topography, and thus, the surface roughness is reduced and the Rs uniformity within a wafer is improved.
Claims13
A method of forming a polysilicon layer, comprising:
- forming a first polysilicon layer on a substrate, wherein the first polysilicon layer is formed by introducing a silicon-containing gas and an inhibitive gas, and the inhibitive gas is for inhibiting a decomposition rate of the silicon-containing gas;
- and
- forming a second polysilicon layer on the first polysilicon layer, wherein the second polysilicon layer is formed by introducing the silicon-containing gas only,
- wherein the silicon-containing gas comprises silane or disilane, and the inhibitive gas comprises hydrogen, and
- wherein a flow rate ratio of the silicon-containing gas to the inhibitive gas is from about 1:50 to about 1:60.
Dependencies are inferred from the claim text.