TY - JOUR
T1 - Photoquenching effect and thermal recovery process for midgap levels in GaAs
T2 - An EL2 family in GaAs
AU - Cho, Hoon Young
AU - Kim, Eun Kyu
AU - Min, Suk Ki
PY - 1989
Y1 - 1989
N2 - We have studied the photocapacitance quenching effect and the thermal recovery process for the EL2 family in heat-treated GaAs. During the heat treatment at 850°C with use of an infrared rapid thermal process, it was identified that EL2, as the main midgap-level defect in GaAs, does not exist alone, but three different midgap levels at 0.73, 0.81, and 0.87 eV below the conduction band coexist with it as a family in various proportions. The EL2 out-diffusion coefficient of 1.02×10-8 cm2/s indicates that EL2 should have a contribution from an interstitial arsenic atom (Asi). These three midgap levels represent a nonexponential quenching transient at 77 K and three activation energies (150, 300, and 350 meV) of the thermal recovery process. Our data indicate that three midgap levels in GaAs make up the EL2 family, each involving a different metastable state. We suggest that three kinds of EL2 could each have their own metastable states and coexist as a family. We conclude that, if EL2 has the atomic structure of AsGa+X, X might be an interstitial arsenic atom (Asi) or a vacancy complex with Asi..AE
AB - We have studied the photocapacitance quenching effect and the thermal recovery process for the EL2 family in heat-treated GaAs. During the heat treatment at 850°C with use of an infrared rapid thermal process, it was identified that EL2, as the main midgap-level defect in GaAs, does not exist alone, but three different midgap levels at 0.73, 0.81, and 0.87 eV below the conduction band coexist with it as a family in various proportions. The EL2 out-diffusion coefficient of 1.02×10-8 cm2/s indicates that EL2 should have a contribution from an interstitial arsenic atom (Asi). These three midgap levels represent a nonexponential quenching transient at 77 K and three activation energies (150, 300, and 350 meV) of the thermal recovery process. Our data indicate that three midgap levels in GaAs make up the EL2 family, each involving a different metastable state. We suggest that three kinds of EL2 could each have their own metastable states and coexist as a family. We conclude that, if EL2 has the atomic structure of AsGa+X, X might be an interstitial arsenic atom (Asi) or a vacancy complex with Asi..AE
UR - http://www.scopus.com/inward/record.url?scp=0038800159&partnerID=8YFLogxK
U2 - 10.1103/PhysRevB.39.10376
DO - 10.1103/PhysRevB.39.10376
M3 - Article
AN - SCOPUS:0038800159
SN - 0163-1829
VL - 39
SP - 10376
EP - 10379
JO - Physical Review B
JF - Physical Review B
IS - 14
ER -