Method and apparatus for precleaning a substrate surface prior to epitaxial growth
Embodiments of the present invention generally relate to methods for removing contaminants and native oxides from substrate surfaces. The methods generally include removing contaminants disposed on the substrate surface using a plasma process, and then cleaning the substrate surface by use of a remote plasma assisted dry etch process.
1. A method for forming an epitaxial layer on a surface of a substrate, comprising:
removing a first portion of carbon containing contaminants from the surface of the substrate, wherein the first portion of the carbon containing contaminants are removed by a hydrogen containing plasma process; then
removing a second portion of the carbon containing contaminants by an oxidizing process, wherein the hydrogen containing plasma process and the oxidizing process are performed in a first processing chamber; then
cleaning the surface of the substrate by use of a fluorine containing plasma etch process in a second processing chamber; and then
forming an epitaxial layer on the surface of the substrate.
2. The method of claim 1 , wherein the hydrogen containing plasma process utilizes an inductively coupled plasma.
3. The method of claim 1 , wherein the hydrogen containing plasma process is performed at a pressure of about 20 mT.
4. The method of claim 1 , wherein the hydrogen containing plasma process utilizes a capacitively coupled plasma with hydrogen containing gas.
5. The method of claim 1 , wherein the hydrogen containing plasma process utilizes a plasma that is energized by a microwave with hydrogen containing gas.
6. The method of claim 1 , further comprising heating the surface of the substrate following the plasma etch process.
7. The method of claim 1 , wherein the fluorine containing plasma etch process comprises flowing NF 3 gas into a remote plasma source.