Preparation And Study Of Zinc Nitride Films

Nitride semiconductor material is a new kind of semiconductor materials, which has larger potential on electronics and optoelectronics Applications. It also has the advantages of high electron mobility and the good conductivity at room temperature. However, the reports of group Ⅱ nitride semiconductors is far less than group Ⅲ nitride semiconductors. Zinc nitride as a group Ⅱ nitride has attracted widely interestingness of researchers, for the influence of electronic structure and 3 D track of Zinc on the valence band. In addition, the preparation method of the p-type zinc oxide be obtained by the situ oxidation of the n-type zinc nitride has become a new and effective method. Since the appearance of zinc nitride film, researchers begin to prepare it by various methods. But the zinc would prefer reacting with the oxygen in the reaction atmosphere to reacting with the nitrogen, which would lead to involuntary oxygen adulteration. So the preparation of zinc nitride film has lots of problems. In this thesis, the zinc nitride films are synthesized on (0001) Sapphire substrate-. quartz substrate and crystal silicon substrate by RF reactive magnetron sputtering and MOCVD. We also studied the influence of different growth conditions on the properties of the thin films.Research work and results are as follows:1. The zinc nitride films were prepared on the Sapphire substrate(0001)、quartz substrate and crystal silicon substrate by the MOCVD. The diethylzinc was the zinc source. The high purity ammonia was the nitrogen source. The high purity nitrogen gas was the carrier and protective gas. The reaction temperature was 370 ℃-450℃and the reaction chamber pressure was 5torr-30torr. The proportion of the source of the group V and the group II was 700:1-1500:1. With the rising of the temperature, the source materials begin to resolve. The Zn3N2(400) diffraction peak appears when the temperature become 400℃. The pre-reaction of diethylzinc would appear with high reaction temperature and it would reduce the growth rate and the crystal quality. By the researching of the films, we find the better condition:the reaction temperature be 400℃, the pressure be 30torr, The proportion of the group V and the group II be 1000:1 and the substrate be the quartz and Sapphire.2. The zinc nitride films were prepared on the Sapphire substrate(0001)、quartz substrate and crystal silicon substrate by the rf-magnetron sputtering. The zinc target was the zinc source. The high purity nitrogen was the nitrogen source, and the argon was the sputtering gas. The reaction temperature was 200℃and the reaction chamber pressure was 6pa-20pa. The sputtering power was 45w-100w and the proportion of the nitrogen and the argon was 1:3,1-1 and 3:1.The film is polycrystal. The result of XPS displays that there are involuntary oxygen adulterations in the films. From the SEM, the crystal grain on the surface of the films prepared on the quart substrate is compact and small, and prepared on the sapphire is bigger. The crystal grain on the surface of the films prepared on the monocrystalline silicon is irregular bulk. The difference indicates that the growth pattern and the crystal orientation of the films prepared on the monocrystalline silicon are different from that on the other substrate. The growth rate of the film is only 15nm/min when the sputtering power is 45w, while the crystal quality is the best. In the reaction, the proportion of the nitrogen and the argon influence the sputtering and the reaction respectively. So the appreciate proportion is one important condition and it is controlled by the sputtering power and pressure.