| Microwave electron cyclotron resonance (MWECR) CVD is a newly developed technique for plasma processing and materials fabrication, such as plasma etching and films deposition. It is until the eighties of the twentieth century the technique applied to prepare films such as diamond, BN and SiC, etc. In this thesis, we first introduced the research on BN films and its development, properties and application of this interesting III- V compound. We tested the ECR deposition system and plasma parameters with the help of Langmuir probe and Faraday cup. The floating potential, electron temperature, ion density and flux density are all varied with the system parameters. The identical parameters we measured in our system is as follows, the electron temperature is from 1 to 4eV, ion density is among the magnitudes of i09-iO? the flux density is about 0.05-0.22J/mAcm2.We prepared BN films with this system, and the mainly results are as follows,1 It was the first time to study the oriented growth of BN films systematically. We discussed the effects of several variables in the experiment on the orientation of the films. The orientation mechanism of the BN films was also probed.A)The orientation of hBN on Si (100) was dominated intrinsically by the crystalline habit and the lattice mismatch between the substrate and films. The former was dominated by the periodical bond chain (PBC) theory, while the latter was in relation with the stress and strain.B)The deposition time may influence the films orientation and growth rate.C)We found that the negative bias or ion bombardment was important to the orientation variation of the films. Low bias is helpful for the basal plane orientation, while under high bias the films shows that the c axis of BN was nearly parallel to the substrate. This result is consistent with those in literature on preparing cBN films.D)We also observed the role of gas species on the orientation of the films. Large amount of Hydrogen was disadvantage to the basal plane orientation, but it is helpful for the c axis paralleling to the substrate. On the other hand, certain amount of Ar is benefit for the basal plane orientation, which is similar to what observed inMWECR CVD ~& BN~I,the deposition of Al.E) With the help of PECVD, we found that high substrate temperature is advantage to the basal plane orientation. Higher temperature helps the particles absorbed on the substrate moved to the location of two-dimension nucleation rapidly. In addition, the growth temperature of films in high substrate temperature process is more similar to that of the single crystal growth in which the hexagonal system shows the sheet growth habit. And, high temperature is good for competition of facets during growth.2 We studied the films with Raman polarization spectrum. The peak intensity in the polarization spectrum of the films with basal plane not oriented on the substrate changes with the polarization condition. We also measure the uv-via spectrum, and find that the band gap of our sample is from 3.5 to 5.6 eV, which is relation to the preparation condition.3 We for the first time prepared hBN-cBN mixed films with the hot filament assisted ECR CVD system. It is suggested that the chemical process plays an important role in the formation of cBN films, however the simultaneous bombardment of certain energy ions is necessary. The role of hot filament may be to active the gas species, however large amount of hydrogen shows negative effects on the formation of cBN.
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