Defect Etch for Silicon Evaluation

Abstract

The Secco etch, with ultrasonic agitation, is widely used to determine dislocation densities in <100> Si. Experiments have shown that under certain conditions, the cavitation of the ultrasonics can generate anomalous defect etch pits. A new defect etch formulation was developed for evaluating <100> Si ingot material which does not require ultrasonic agitation. It consists of . The etching time compared to Secco etch with ultrasonics is reduced by one‐half in developing etch pits of equivalent size. This composition is useful for revealing dislocations in 0.6–15 Ωcm n‐ and p‐type silicon. In addition, dislocation etch pits are readily developed in more heavily doped <100> Si crystals using a mixture of.