Observation of Surface Defects in Electrolytically Etched Silicon by Infrared Microscopy

Infrared microscopy has been used to observe tunnel networks in anodically etched silicon. The etch networks on (111) silicon originate at surface defects and lie along 〈110〉 directions in (111) planes. The technique described offers considerable promise as a quick and simple room-temperature method for surface evaluation. A comparison is made of the defect structure revealed using electrolytic etching with that revealed by high-temperature copper-decoration techniques.