Semiconductor process
AssigneeUnited Microelectronics Corp.
InventorsChun-Wei Yu, Kuang-Hsiu Chen, Chueh-Yang Liu, Yu-Ren Wang
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Abstract
A semiconductor process including the following steps is provided. An epitaxial layer is formed on a substrate. An oxide layer is formed on the epitaxial layer, wherein the oxide layer includes a chemical oxide layer, a high-temperature oxide (HTO) layer or a surface modification oxide layer. An ion implant process is performed to the epitaxial layer to form a doped region in the epitaxial layer. The oxide layer is removed by using a diluted hydrofluoric acid (DHF) solution after performing the ion implant process, wherein a volume ratio of water to a hydrofluoric acid (HF) in the DHF solution is 200:1 to 1000:1.
Claims16
A semiconductor process, comprising:
- forming an epitaxial layer on a substrate;
- forming an oxide layer on the epitaxial layer, wherein the oxide layer comprises a chemical oxide layer, a high-temperature oxide (HTO) layer or a surface modification oxide layer;
- performing an ion implant process to the epitaxial layer to form a doped region in the epitaxial layer;
- and
- removing the oxide layer by using a diluted hydrofluoric acid (DHF) solution after performing the ion implant process, wherein a volume ratio of water to a hydrofluoric acid (HF) in the DHF solution is 200:1 to 1000:1,
- wherein the epitaxial layer is a silicon-phosphorus (SiP) epitaxial layer, and a depth of a divot of the SiP epitaxial layer is less than 30 angstroms after removing the oxide layer.
Dependencies are inferred from the claim text.