Method for forming a multiple layer passivation film and a device incorporating the same
View Patent ↗A method of forming a multiple layer passivation film on a semiconductor device surface comprises placing a semiconductor device in a chemical vapor deposition reactor, introducing a nitrogen source into the reactor, introducing a carbon source into the reactor, depositing a layer of carbon nitrogen on the semiconductor device surface, introducing a silicon source into the reactor after the carbon source, and depositing a layer of silicon carbon nitrogen on the carbon nitrogen layer. A semiconductor device incorporating the multiple layer passivation film is also described.
1. A method of forming a multiple layer passivation film on a semiconductor device surface, comprising:
placing a semiconductor device in a deposition reactor;
introducing a nitrogen source into the reactor;
introducing a carbon source into the reactor;
depositing an interfacial layer on a surface of the semiconductor device, the interfacial layer comprising carbon and nitrogen and being substantially devoid of silicon;
introducing an additional source into the reactor after the interfacial layer has been deposited on the surface of the semiconductor device; and
depositing an environmentally robust cover layer on the interfacial layer, wherein the additional source is a silicon source, and wherein the cover layer comprises silicon, carbon, and nitrogen.
2. The method of claim 1 , wherein the silicon source is introduced at least 15 seconds after the interfacial layer has been depositing.
3. The method of claim 2 , wherein the source of the nitrogen is chosen from nitrogen gas and ammonia, the source of the carbon is chosen from methane, ethane, butane, propane, and a liquid hydrocarbon source used in a bubbler with nitrogen (N2) as a carrier gas, and the source of the silicon is chosen from silane and Tretra-Ethyl-OrthoSilicate (TEOS).
4. The method of claim 2 , wherein the source of the carbon is chosen from contamination from a wall of the chemical vapor deposition reactor chamber walls and the semiconductor device surface.
5. The method of claim 2 , wherein the nitrogen source and the carbon source form reactive species to form the interfacial layer of carbon nitrogen on the semiconductor device surface before the silicon source is introduced.
6. The method of claim 5 , wherein the nitrogen source, the carbon source, and the silicon source form reactive species to form the cover layer of silicon, carbon, and nitrogen over the semiconductor device surface.
7. The method of claim 6 , wherein the nitrogen source is introduced at a flow rate of about 2000 standard cubic centimeters per minute (sccm), the carbon source is introduced at a flow rate of about 210 sccm and the silicon source is introduced at a flow rate of about 105 sccm.
8. The method of claim 7 , further comprising suspending the flow of the nitrogen source after a predetermined amount of time to form an additional layer over the cover layer.
9. The method of claim 6 , wherein a first part of the cover layer of silicon carbon nitrogen is formed at a temperature of approximately 100 degrees Celsius and radio frequency (RF) reactor power of approximately 10 W.
10. The method of claim 9 , wherein after the interfacial layer and first part of the cover layer have been grown at 100 degrees Celsius and allowed to stabilize, then depositing a densified layer of silicon carbon nitrogen at approximately 300 degrees Celsius.
11. The method of claim 10 , wherein the cover layer of silicon, carbon, and nitrogen and the additional layer are formed using a plasma enhanced chemical vapor deposition (PECVD) reactor.
12. The method of claim 6 , wherein the introduction of the carbon source prior to the introduction of the silicon source when forming the interfacial layer prevents reactive species released from the silicon source from causing defects in the semiconductor device surface.
13. The method of claim 1 , wherein the semiconductor surface is chosen from silicon, germanium, gallium arsenide, indium phosphide, aluminum nitride, indium antimony and combinations thereof.
14. A method of forming a multiple layer passivation film on a semiconductor device surface, comprising:
placing a semiconductor device in a deposition reactor;
introducing a nitrogen source into the reactor;
introducing a carbon source into the reactor;
depositing a layer of carbon nitrogen (CN) on the semiconductor device surface;
introducing an additional source into the reactor after the carbon source; and
depositing an environmentally robust cover layer on the carbon nitrogen layer, wherein the additional source is a silicon source and the cover layer is silicon carbon nitrogen (SCN), wherein the silicon source is introduced after the carbon source has been depositing for a predetermined amount of time, and wherein the predetermined amount of time is approximately between 15 seconds and 3 minutes.
15. A method of forming a multiple layer passivation film for a semiconductor, comprising:
placing a semiconductor photodetector in a chemical vapor deposition reactor;
introducing a nitrogen source into the reactor;
introducing a carbon source into the reactor;
depositing a layer of carbon nitrogen;
introducing a silicon source into the reactor after the carbon source; and
depositing a layer of silicon carbon nitrogen, wherein the silicon source is introduced after the carbon source has been flowing for a predetermined amount of time, and wherein the nitrogen source, the carbon source and the silicon source form reactive species of nitrogen, carbon and silicon, respectively, and form an interfacial layer of carbon nitrogen over the semiconductor prior to forming a cover layer of silicon carbon nitrogen over the interfacial layer, and wherein the nitrogen source is introduced at a flow rate of about 2000 standard cubic centimeters per minute Csccm), the carbon source is introduced at a flow rate of about 210 sccm and the silicon source is introduced at a flow rate of about 105 sccm.
16. The method of claim 15 , wherein the cover layer of silicon carbon nitrogen is formed at a temperature of approximately 100 degrees Celsius and wherein after the interfacial layer and cover layer are grown at approximately 100 degrees Celsius and allowed to stabilize, the method further comprising depositing a densified layer of silicon carbon nitrogen at approximately 300 degrees Celsius.
17. The method of claim 16 , further comprising suspending the flow of the nitrogen source after a predetermined amount of time to form an additional layer of silicon carbide over the cover layer of silicon carbon nitrogen.
18. A method, comprising:
(a) contacting, in the substantial absence of silicon, a semiconductor device with carbon and nitrogen to deposit a carbon- and nitrogen-containing interfacial layer on a surface of the semiconductor device; and
(b) after deposition of the interfacial layer, contacting the semiconductor device with silicon to form a cover layer on the interfacial layer, the cover layer comprising silicon, carbon, and nitrogen.
19. The method of claim 18 , wherein, in the contacting (b), the semiconductor device is also contacted with carbon and nitrogen, wherein the cover layer comprises silicon, carbon, an nitrogen, and wherein the contacting steps (a) and (b) are performed in the presence of a plasma.
20. The method of claim 18 , wherein the thereafter contacting step is performed at a first temperature and further comprising:
(c) after contacting step (b), increasing a temperature of the semiconductor device at a second temperature higher than the first temperature;
(d) contacting the semiconductor device with nitrogen and carbon in the presence of a plasma and in the substantial absence of silicon to form a carbon- and nitrogen-containing layer; and
(e) contacting the semiconductor device with carbon and silicon in the presence of a plasma and in the substantial absence of nitrogen to form a carbon- and silicon-containing layer.