ISSN:
1089-7550
Source:
AIP Digital Archive
Topics:
Physics
Notes:
The effects of substrate temperature on the donor ionization energy and on the electrical and photoluminescent properties of selectively doped short-period GaAs:Si/AlAs superlattices are studied. The superlattice structure is characterized by means of double-crystal x-ray diffraction. It is found that the interface between the GaAs and AlAs layers slightly degrades even at a low substrate temperature of 550 °C, and that the degradation is enhanced with an increase in the substrate temperature. The Si donor level is still shallow for substrate temperatures lower than 600 °C, since only a slight degradation occurs in this temperature range. However, the Si donor forms an excess deep DX center near the interface region for higher substrate temperatures. Accordingly, the donor binding energy increases with increasing substrate temperature, since the contribution from the mixed interface region becomes larger. With an increase in the substrate temperature, the photoluminescence peak intensity increases, although the electron concentration at room temperature decreases. This phenomenon is discussed in relation to the formation of donorlike deep levels in AlAs/GaAs short-period superlattices.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1063/1.339551
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