Defect energy levels in p-type GaAsBi and GaAs grown by MBE at low temperatures
Defect energy levels in p-type GaAsBi and GaAs grown by MBE at low temperatures
复制标题
DOI：
10.1088/0268-1242/31/6/065007
复制
发表时间：
2016-06-01
影响因子：
1.9
通讯作者：
Masnadi-Shirazi, M.
中科院分区：
文献类型：
--
作者：
Mooney, P. M.;Tarun, M. C.;Masnadi-Shirazi, M.
用深能级瞬态谱研究了在330 ℃和370 ℃衬底温度下用分子束外延生长的p型GaAs_（1-x）Bix（x < 1%）和GaAs中的深能级缺陷。我们发现，在330摄氏度下将Bi掺入GaAs中不会影响空穴陷阱的总浓度，其类似于4 × 10（16）cm（-3），与在具有类似合金成分的Si掺杂的GaAsBi中观察到的电子陷阱浓度相当。将p型GaAsBi（x = 0.8%）层的生长温度从330摄氏度提高到370摄氏度，空穴陷阱浓度降低了一个数量级。此外，具有接近中间带隙能级的缺陷是最有效的非辐射复合中心，仅存在于在较低温度下生长的GaAsBi层中。这些新的结果进行了讨论的背景下，在类似的条件下生长的n型GaAs和GaAsBi层的先前测量。
Deep level defects in p-type GaAs1-xBix (x < 1%) and GaAs grown by molecular beam epitaxy at substrate temperatures of 330 degrees C and 370 degrees C have been characterized by deep level transient spectroscopy. We find that incorporating Bi into GaAs at 330 degrees C does not affect the total concentration of hole traps, which is similar to 4 x 10(16) cm(-3), comparable to the concentration of electron traps observed in Si-doped GaAsBi having a similar alloy composition. Increasing the growth temperature of the p-type GaAsBi (x = 0.8%) layer from 330 degrees C to 370 degrees C reduces the hole trap concentration by an order of magnitude. Moreover, the defects having near mid-gap energy levels that are the most efficient non-radiative recombination centers are present only in GaAsBi layers grown at the lower temperature. These new results are discussed in the context of previous measurements of n-type GaAs and GaAsBi layers grown under similar conditions.