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Revealing of the transition from n- to p-type conduction of InN:Mg by photoconductivity effect measurement.

ABSTRACT: We report evidence of the transition from n- to p-type conduction of InN with increasing Mg dopant concentration by using photoconductivity (PC) measurement at room temperature. This transition is depicted as a conversion from negative to positive PC under above-bandgap optical excitation. The n- to p-type transition in InN:Mg is further confirmed by thermopower measurements. PC detection method is a bulk effect since the optical absorption of the surface electron accumulation is negligibly low due to its rather small thickness, and thus shows advantage to detect p-type conduction. This technique is certainly helpful to study p-type doping of InN, which is still a subject of discussions.

SUBMITTER: Guo L

PROVIDER: S-EPMC3952149 | biostudies-other | 2014

REPOSITORIES: biostudies-other

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