Influence of annealing conditions on impurity species in arsenic-doped HgCdTe grown by molecular beam epitaxy

• 来源期刊: 中国物理B（英文版）
• 关键词: As-doped HgCdTe annealing influence extrinsic/intrinsic impurities modulated photoluminescence spectra
• 年，卷（期）: 2010,（11）
• 页码范围: 555-561
• 页数: 7页
• 语种: 英文

摘要

Based on our previous work, the influence of annealing conditions on impurity species in in-situ arsenic (As)doped Hg1-x>Cdx>Te (x≈0.3) grown by molecular beam epitaxy has been systematically investigated by modulated photoluminescence spectra. The results show that (I) the doped-As acting as undesirable shallow/deep levels in as grown can be optimized under proper annealing conditions and the physical mechanism of the disadvantage of high activation temperature, commonly assumed to be more favourable for As activation, has been discussed as compared with the reports in the As-implanted HgCdTe epilayers (x≈0.39), (ii) the density of VHg> has an evident effect on the determination of bandgap (or composition) of epilayers and the excessive introduction of VHg will lead to a short wavelength shift of epilayers, and (iii) the VHg prefers forming the VHg-AsHg complex when the inactivated-As (AsHg>or related) coexists in a certain density, which makes it difficult to annihilate VHg in As-doped epilayers. As a result, the bandedge electronic structures of epilayers under different conditions have been drawn as a brief guideline for preparing extrinsic p-type epilayers or related devices.