| Abstract: | The dependence of the optical quality, i.e. the line width and homogeneity of (1 1 0) oriented quantum wells on the substrate temperature, the As pressure as well as on the As
species is studied by means of micro-photoluminescence. Molecular beam epitaxial growth using the As
dimer leads to a photoluminescence line width as narrow as 5.5 meV for 7 nm wide quantum wells compared to a value of 8 meV for the As
tetramer source. In addition to the small line widths which can be achieved using As
, quantum wells grown under these conditions are also superior to those using As
in terms of uniformity on a
m length scale. In contrast, the peak mobility of a two-dimensional electron system located at a (1 1 0) oriented GaAs/AlGaAs heterointerface of
cm
V s is obtained for tetramer growth, while the use of As
degrades the electron mobility to values below 500 000 cm
V s. |
