Positron study of native vacancies in doped and undoped GaAs
Positron study of native vacancies in doped and undoped GaAs
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DOI：
10.1088/0022-3719/19/3/004
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发表时间：
1986-01
期刊：
影响因子：
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通讯作者：
G. Dlubek;O. Brümmer;F. Plazaola;P. Hautojärvi
中科院分区：
文献类型：
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作者：
G. Dlubek;O. Brümmer;F. Plazaola;P. Hautojärvi
正电子寿命测量用于研究生长状态下的各种掺杂和未掺杂的 GaAs 样品。在未掺杂的 GaAs 中，作者检测到空位缺陷，其浓度在整个样品中各不相同，约为 1018 cm-3。在等时退火过程中，缺陷在 500 摄氏度时消失。讨论了空位缺陷的性质，并将其行为与非化学计量缺陷和辐射缺陷进行了比较。结论是，在未掺杂的 GaAs 中观察到的捕获正电子的缺陷是中性的 As 空位。观察了掺杂对正电子寿命影响的系统趋势。 n 型 GaAs 的寿命值比 p 型 GaAs 高 10-20 ps。这种效应归因于受主型Ga-空位-掺杂剂复合物的正电子捕获。
Positron lifetime measurements are used to study various doped and undoped GaAs samples in the as-grown state. In undoped GaAs the authors detect vacancy defects, the concentration of which varies across the sample and is of the order of 1018 cm-3. During isochronal annealing the defects disappear at 500 degrees C. The nature of the vacancy defects is discussed and their behaviour is compared with those of non-stoichiometric defects and radiation defects. It is concluded that the defects observed to trap positrons in undoped GaAs are neutral As vacancies. Systematic trends of the doping effects on positron lifetime are observed. The lifetime values in n-type GaAs are 10-20 ps higher than in p-type GaAs. This effect is attributed to positron trapping by acceptor-type Ga-vacancy-dopant complexes.