| The band gap of the MgZnO alloy composed of MgO and ZnO can be changed in the range from 3.3 ～7.9 eV. This material has potential applications in short wavelength opto-electronic devices. ZnO/Zn1-xMgxO quantum wells and superlattices can be used in the semiconductor laser, photodetectors and other opto-electronic devises.In our experiments, we deposited Zn0.9Mg0.1O thin films on Si(100) substrates and Si(100) substrates with ZnO buffer layer by pulsed laser deposition(PLD), respectively, and systematically studied the growing parameters of ZnMgO films, such as substrate temperature, laser repetition, oxygen pressure, time and so on. And for the first time, we deposited ZnO/ZnMgO heterojunction and superlattice on Si(100) and Si/ZnO substrates. Our work is as below:1. Recently, most of ZnMgO alloy were synthesized on sapphire or ScAlMgO4. In our report, ZnMgO alloy were synthesized on silicon by PLD and for the first time we finded the suitable growing parameters to get high quality and optical properties ZnMgO thin films. The optimized conditions of growing ZnMgO films on Si (100) substrate by PLD is concluded:substrate temperature 600℃, oxygen pressure 10Pa, laser repetition 3Hz and substrate-to-target distance 4.5cm.2. The high crystalline quality hexagonal ZnMgO films on Si(100) have been grown using ZnO buffer layer, with the FWHM of (002) peak by X-ray Diffraction is 0.2044o and its pictures by Field Emission Scanning Electron Microscopy.3. PLD was emplyed to prepare ZnO/Zn1-xMgxO heterojunction and quantum wells directly on Si(100) substrate for the first time in China. Simultaneously we studied the crystal quality and optical properties of multi-layer structures.4. Improve the crystal quality of multi-layer structure by using ZnO as buffer layer to solve the lattice mismatch problem. We finally got the the multi-layer with smooth surface and clear cross-sectional morphology.
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