(a) Formation of Stranski–Krastanow islands along tungsten lines at ( deposition). (b) Formation of mesa ridges in between lines at ( deposition). (c) Overgrown circle showing preferential overgrowth direction to be 30° of the  direction, corresponding to grating directed at 30° from the direction ( deposition). (d) SEM image of cross section of the overgrown ( deposition) tungsten pattern, with two tungsten lines shown as white contrast.
TEM images of (a) interface between InAs and GaAs of the reference device. (b) Interface between of the overgrown structure. The arrows mark the SK island and the threading dislocation, originating from the island. The interface of the metal patterned device is smoother and leads to less stacking faults at the interface in between the metal pattern structure.
characterizations of the overgrown devices. (a) Layout of the directions on the sample. (b) Schematic structure of the overgrown devices. (c) characteristics of overgrown devices and references. Numbers in the legend stand for the period of the -wide tungsten lines.
Hall effect measurement results: (a) carrier density and (b) mobility as a function of the tungsten coverage.
Article metrics loading...
Full text loading...