Carrier Profiling of a Heterojunction Bipolar Transistor and p–i–n Photodiode Structures by Electrochemical C–V Technique

Carrier profiling of GaAs/GaAlAs multilayer structures (heterojunction bipolar transistor and heterojunction p-i-n photodiode) by electrochemical capacitance-voltage technique is described. Optimum measurement parameters (electrolyte type, etching and measurement voltages, etc.) are established. The results are compared with those of spreading resistance profiling and transmission electron microscopy. Some specific problems are discussed.