11-05-2017 дата публикации
Номер: US20170133460A1
Принадлежит:
The present invention provides a method for forming a semiconductor structure, including: first, a substrate is provided. Next, at least two gate structures are formed on the substrate, each gate structure including two spacers disposed on two sides of the gate structure. Afterwards, a dry etching process is performed to remove parts of the substrate, so as to form a recess in the substrate, and a wet etching process is performed, to etch partial sidewalls of the recess, so as to form at least two tips on two sides of the recess respectively. In addition, parts of the spacer are also removed through the wet etching process, and each spacer includes a rounding corner disposed on a bottom surface of the spacer. 1. A method for forming a semiconductor structure , comprising:providing a substrate;forming at least two gate structures on the substrate, each gate structure including two spacers disposed on two sides of the gate structure;performing a dry etching process, to remove parts of the substrate, so as to form a recess in the substrate; andperforming a wet etching process, to etch partial sidewalls of the recess, so as to form at least two tips on two sides of the recess respectively, in addition, parts of the spacer are also removed through the wet etching process, and each spacer comprises a rounding corner disposed on a bottom surface of the spacer.2. The method of claim 1 , further comprising performing an ion implantation process on a bottom surface of the recess after the dry etching process is performed.3. The method of claim 2 , wherein the wet etching process is performed after the ion implantation process is performed.4. The method of claim 2 , wherein the ions used in the ion implantation process comprise boron ions claim 2 , phosphate ions claim 2 , arsenic ions claim 2 , germanium ions claim 2 , argon ions or a combination thereof.5. The method of claim 1 , wherein the recess is disposed in the substrate and between the two gate structures.6. The ...
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