Achievement of low-resistivity p-type ZnSe and the role of twinning

Past literature is replete with reports of well-conducting p-type ZnSe; however, such reports have either been poorly reproducible and/or have shown puzzling features which are incompatible with accepted semiconductor theory (e.g., p-type behavior via n-type dopants, better light emitting diodes from high-resistivity material, etc.). We have recently noted that ‘‘good’’ p-type material available to us has been heavily twinned, and moreover has shown ‘‘nonstandard’’ electrical behavior such as a negative differential resistivity. In the present paper the earlier literature is reanalyzed based on the concept that to date such p-type material has probably always been heavily twinned. A far improved understanding of the earlier work is obtained via the insight gained from these recent (twinning) results.