Defects in highly doped silicon investigated by combined current and capacitance DLTS

By using a recently developed method based on Deep-Level Transient Spectroscopy (DLTS) we can characterize electrically active defects in highly doped regions of silicon devices. The main advantage of the method is its applicability to nonabrupt p-n junctions for investigating impurities, where traditional DLTS fails. The structures investigated were emitter-base p-n junctions with phosphorus doped emitter and gallium or boron doped p base with varying concentrations. Using this DLTS method we have studied the development of generation centers gettered to phosphorus emitter regions as they go from isolated centers at lower phosphorus concentrations into defect clusters at higher phosphorus concentrations.