Insulating layer next to fin structure and method of removing fin structure
A method of removing a fin structure includes providing a substrate. A fin structure extends from the substrate. A mask layer is disposed on a top surface of the fin structure. An organic dielectric layer covers the substrate, the fin structure and the mask layer. A first etching process is performed to entirely remove the mask layer by taking the organic dielectric layer as a mask. Then a second etching process is performed to remove the fin structure. The first etching process is preferably an anisotropic etching process, and the second etching process is an isotropic etching process.
1. A method of removing a fin structure, comprising:
providing a substrate, and a fin structure extending from the substrate, wherein a mask layer is disposed on a top surface of the fin structure, and an organic dielectric layer covers the substrate, the fin structure and the mask layer;
patterning the organic dielectric layer to form an opening on the organic dielectric layer, wherein the mask layer is exposed by the opening;
performing a first etching process to entirely remove the mask layer by taking the organic dielectric layer as a mask, wherein part of the fin structure is removed during the first etching process; and
performing a second etching process to remove the fin structure.
2. The method of removing a fin structure of claim 1 , wherein one third of the fin structure is removed during the first etching process.
3. The method of removing a fin structure of claim 1 , wherein the second etching process further comprises:
partly removing the substrate to form a recess in the substrate.
4. The method of removing a fin structure of claim 1 , wherein the first etching process is an anisotropic etching process.
5. The method of removing a fin structure of claim 4 , wherein the first etching process is a dry etching process.
6. The method of removing a fin structure of claim 1 , wherein the second etching process is an isotropic etching process.
7. The method of removing a fin structure of claim 6 , wherein the second etching process is a wet etching process or an isotropic dry etching process.