Kinetic stabilization of Fe ultra-thin film on GaAs(100) grown at low temperature

We grew ultra-thin Fe films on GaAs(100) at low temperature (around 130K) to suppress chemical reactions between Fe and substrate atoms (interface alloying and As- surface segregation). For various Fe film thickness ranging from 1 to 30$\AA$, we preformed photoemission experiment using synchrotron radiation to characterize the growth kinetics, and compared them with Fe films of similar thickness grown at room temperature. We confirmed that the interface alloying is obviously decreased at low temperature, and the surface segregation of As is blocked when Fe film is grown around 130K. As a result, more abrupt interface can be obtained in the low temperature growth. Furthermore, these Fe films grown at low temperature are found to be stable against As segregation even when the sample is annealed up to room temperature.