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Studies on deep levels in GaAs epilayers grown on Si by metal-organic chemical vapour deposition, Part II: 1.13 eV photoluminescence emission
| Content Provider | Semantic Scholar |
|---|---|
| Author | Zhao, Jian Lian Gao, Yizhi Liu, Xiaoyan Huang, S. H. Yu, Jiang-Miao Liang, J. C. |
| Copyright Year | 1994 |
| Abstract | In recent years, the optical properties of heteroepitaxial GaAs layers grown on Si substrates have been studied extensively because of their potential applications for integrated circuits and optoelectronics [1-4]. It has been reported that the larger misfit of lattice constants (4.1%) and discrepancies of thermal expansion coefficients of GaAs and Si cause stresses on the interface, leading to the creation of various defects. Deep levels originating from the stoichiometric defects, interracial defects and surface states can strongly degrade the crystalline quality and deteriorate the optical and electrical properties of heterostructures. Recently, we reported studies on deep levels in epitaxial GaAs grown on Si by metal-organic chemical vapour deposition (MOCVD) and identified that the 1.04 eV emission could be explained well by the recombination luminescence of a negatively charged arsenic vacancy donor and a next-nearest neighbour gallium vacancy acceptor [5]. In this work, we did photoluminescence (PL) investigations of the 1.13 eV emission band at 77 K present in GaAs epilayers grown on Si with respect to changes of temperature and excitation intensity. We identified that the 1.13 eV emission originates from the recombination of a donor-acceptor pair (DAP), composed of an Si shallow donor on Ga site and a next-nearest neighbour Ga vacancy acceptor, and used a configuration coodinate model to locate the donor and acceptor level. GaAs epitaxial layers used in the experiment were grown on 4 ° off toward [110] (100) n-type Si substrates using the two-step method [2] by MOCVD. The Si substrates were chemically treated in NH4OH, H202, H20 and HC1, H202, H20, and etched in HF for i min. In an H2/AsH3 ambient, they were heated initially at 950 °C for 10 min, and the temperature was lowered to 450 °C for GaAs buffer growth with thickness of 25 nm. Trimethylgallium (TMG) and arsine in hydrogen were used as source chemicals. Then the temperature was raised |
| Starting Page | 1694 |
| Ending Page | 1696 |
| Page Count | 3 |
| File Format | PDF HTM / HTML |
| DOI | 10.1007/BF00451743 |
| Volume Number | 13 |
| Alternate Webpage(s) | http://ir.ciomp.ac.cn/bitstream/181722/25481/1/Zhao-1994-STUDIES%20ON%20DEEP%20LEVE.pdf |
| Alternate Webpage(s) | https://doi.org/10.1007/BF00451743 |
| Language | English |
| Access Restriction | Open |
| Content Type | Text |
| Resource Type | Article |
