Variable frequency microwave (VFM) processes and applications in semiconductor thin film fabrications
Methods and apparatus for processing a substrate are described herein. A vacuum multi-chamber deposition tool can include a degas chamber with both a heating mechanism and a variable frequency microwave source. The methods described herein use variable frequency microwave radiation to increased quality and speed of the degas process without damaging the various components.
1. A method for processing a substrate, comprising:
depositing an uncured layer comprising a polymer over a surface of a substrate; and
performing a hard-cure of the uncured layer in a processing chamber, the hard-cure comprising:
heating at least the uncured layer to a degas temperature ranging from about 85 degrees Celsius to about 95 degrees Celsius, the degas temperature being less than a hard-cure temperature for the uncured layer; and
delivering microwave radiation at a variable frequency from a source of microwave radiation to the uncured layer to heat the uncured layer to the hard-cure temperature.
2. The method of claim 1 , wherein the hard-cure temperature is between 300 degrees Celsius and 400 degrees Celsius.
3. The method of claim 1 , further comprising depositing a seed layer.
4. The method of claim 1 , further comprising setting the processing chamber to a hard-cure pressure, wherein the hard-cure pressure is less than 100 mTorr.
5. The method of claim 1 , wherein the variable frequency comprises two or more frequencies, each frequency varying from the previous frequency by from 200 MHz to 280 MHz.
6. The method of claim 1 , wherein the variable frequency changes over a period time.
7. The method of claim 6 , wherein the period of time is between 6 minutes and 10 minutes.
8. A method for processing a substrate, comprising:
depositing an uncured layer comprising a polymer over a surface of a substrate; and
performing a hard-cure of the uncured layer in a processing chamber, the hard-cure comprising:
heating at least the uncured layer to a degas temperature ranging from about 85 degrees Celsius to about 95 degrees Celsius, the degas temperature being less than a hard-cure temperature for the uncured layer; and
delivering microwave radiation at a variable frequency from a source of microwave radiation to the uncured layer to heat the uncured layer to the hard-cure temperature, wherein the variable frequency ranges from about 5.85 GHz to about 7.0 GHz.
9. The method of claim 8 , wherein the hard-cure temperature is between 300 degrees Celsius and 400 degrees Celsius.
10. The method of claim 8 , further comprising setting the processing chamber to a hard-cure pressure, wherein the hard-cure pressure is less than 100 mTorr.
11. The method of claim 8 , wherein the variable frequency comprises two or more frequencies, each frequency varying from the previous frequency by from 200 MHz to 280 MHz.
12. The method of claim 8 , wherein the variable frequency changes over a period time.
13. The method of claim 12 , wherein the period of time is between 6 minutes and 10 minutes.
14. A method for processing a substrate, comprising:
depositing an uncured layer comprising a polymer, an epoxy or combinations thereof over a surface of a substrate; and
performing a hard-cure of the uncured layer in a processing chamber, the hard-cure comprising:
heating at least the uncured layer to a degas temperature ranging from about 85 degrees Celsius to about 95 degrees Celsius, the degas temperature being less than a hard-cure temperature for the uncured layer;
setting the processing chamber to a hard-cure pressure, the hard-cure pressure being under 100 mTorr; and
delivering microwave radiation at a variable frequency from a source of microwave radiation to the uncured layer to heat the uncured layer to the hard-cure temperature, and wherein the degas temperature, the hard-cure pressure and the microwave radiation act in conjunction to produce a cured and degassed layer.
15. The method of claim 14 , wherein the hard-cure temperature is between 300 degrees Celsius and 400 degrees Celsius.
16. The method of claim 14 , wherein the hard-cure pressure is less than 1 mTorr.
17. The method of claim 14 , wherein the variable frequency comprises two or more frequencies, each frequency varying from the previous frequency by from 200 MHz to 280 MHz.
18. The method of claim 14 , wherein the variable frequency changes over a period time.
19. The method of claim 18 , wherein the period of time is between 6 minutes and 10 minutes.
20. The method of claim 14 , further comprising flowing an inert gas into the processing chamber to clear the processing chamber of outgassed substances.