| Ballistic electron emission microscopy, or BEEM, is a technique used to examine metal-semiconductor contacts on a scale of several nanometers or less. In this work we will use the BEEM technique in several areas of interest. BEEM can be used as a feedback tool for process development, as we demonstrate by evaluating the uniformity of MBE-grown AlInAs on a nanometer scale. BEEM can be used to evaluate proposed physical models of current transport, as we discuss in our study of pinch-off effect in Au on GaAs. Also, we will show for the first time that BEEM can be used to observe variations in barrier height in a Schottky contact made to a cleaved GaAs/AlGaAs multilayer cross-section. The cleaved cross-sectional BEEM technique is useful for calibrating resolution as well as for comparing effects of different semiconductor properties on transport. |
