We have studied the effect of low-index channeling on sidewall dry-etch damage. A quantum electron beam in the two-dimensional electron gas of a GaAs/AlGaAs heterostructure was used to probe electrical damage at a specific depth down an etched sidewall. In analyzing the measured behavior as a function of etch time we have developed a model for the sidewall damage distribution that takes into account the geometry of the 〈110〉 channels in detail. The analysis shows that more damage is possible beneath regions of high topography than is usually assumed.
- radiation damage