抄録
We have demonstrated the growth of the GaN film by near-atmospheric plasma-assisted chemical vapor deposition (AP-CVD). Pure nitrogen plasma can be generated stably using an alternating pulsed voltage system that applies an alternating pulsed voltage between two parallel plate electrodes. Using this plasma as a nitrogen source, we can obtain crystalline GaN film above 330℃. Blow 330℃, GaN film was amorphous structure due to carbon contamination. To overcome this issue, hydrogen diluted nitrogen gas was used as reactive gas. Optical emission spectrum measurement revealed that the hydrogen diluted nitrogen near-atmospheric plasma decomposed triethylgallium (TEG), which was used as Ga metal precursor, even at room temperature. Using this plasma as a nitrogen source, deposited GaN films showed the epitaxial growth on a sapphire substrate above the growth temperature of 170℃. From the results obtained, we found that AP-CVD has a great potential of being employed in GaN film fabrication under high nitrogen partial pressure and at low temperature.
