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对于处在亚稳态生长区域内阱宽为15um锗组分x=0．25、0．33、0．40的单量子阱样品，及阱宽相同x=0．45、0．53的单量子阱样品，首先通过喇曼光谱测量了样品的应变弛豫程度，发现当锗组分增加到X≥0．45时，其应变开始逐渐弛豫，然后通过测量深能组瞬态谱（DLTS），研究应变弛豫程度不同的样品中形成的缺陷性质。在X=0.25、0.33、0．40样品中均可以观察到量子阱中载流子发射产生的DLTS峰，由它求得的能带们移值与理论预计值符合。对于X=0．45、0．53样品阱中载流子发射信号已被缺陷信号淹没，表明此时样品的缺陷浓度很大。相应的缺陷情况是：对于应变未弛豫的样品（X=0．25），DLTS测得的缺陷为一点缺陷；对于应变基本未弛豫的样品（X=0．33、0．40）DLTS测得的缺陷主要为一组界面缺陷；而应变部分弛豫的样品（X=0．45、0．53），DLTS测得的缺陷与前三种样品不同，样品的缺陷可能与形成的穿透位错有关。通过电化学腐蚀，可以确定这些缺陷均位于异质界面附近。
For a single quantum well sample with a well width of 15 μm germanium component x = 0.25, 0.33, 0.40 in a metastable growth region and a single well sample with the same well width x = 0.45, 0.53 Quantum well samples were first measured by Raman spectroscopy to determine the degree of strain relaxation and found that when the germanium composition increases to X ≥ 0.45, the strain begins to relax gradually, and then by measuring the deep group transient spectroscopy (DLTS ), The defect nature of the samples formed at different degrees of strain relaxation was investigated. The DLTS peak generated by carrier emission in the quantum well can be observed in X = 0.25, 0.33 and 0.40 samples, and the band shift values obtained by the calculated values agree well with the theoretical ones. For the X = 0.45, 0.53 sample well, the carrier emission signal has been submerged by a defect signal, indicating that the sample has a high defect concentration at this time. The corresponding defect cases were: a defect detected by the DLTS as a slight defect for a sample in which the strain was not relaxed (X = 0.25); a sample (X = 0.33, 0.40) substantially not relaxed for the strain DLTS The defects detected mainly consisted of a set of interfacial defects. For the strain partially relaxed samples (X = 0.45, 0.53), the defects detected by DLTS were different from those of the first three samples. Dislocation related. By electrochemical etching, it can be confirmed that these defects are located near the heterogeneous interface.