In connection with many operational aspects of surface‐based GaAs devices, such as the lifetime of MESFETS,1 it is useful to explore simple possibilities of surface tests. Here, the observed light emission along the periphery of Schottky contacts on GaAs is investigated in view of such an analytical test facility. Additionally, it should be noted that one has the possibility of studying the surface effects on the two relevant phenomena responsible for this light emission: avalanching due to electrons or holes, electroluminescence due to hot charge carriers. We initially present the essential experimental data, then adopt the theory of Wolff 2 for our system of light emission, and finally present additional experimental observations and use them to suggest further efforts on this subject.