Boron Phosphide Films by Reactive Sputtering: Searching for a P-Type Transparent Conductor

Andrea Crovetto, Jesse Adamczyk, Rekha Schnepf, Craig Perkins, Hannes Hempel, Sage Bauers, Eric Toberer, Adele Tamboli, Thomas Unold, Andriy Zakutayev

Research output: Contribution to journalArticlepeer-review

9 Scopus Citations


With an indirect band gap in the visible and a direct band gap at a much higher energy, boron phosphide (BP) holds promise as an unconventional p-type transparent conductor. This work reports on reactive sputtering of amorphous BP films, their partial crystallization in a P-containing annealing atmosphere, and extrinsic doping by C and Si. The highest hole concentration to date for p-type BP (5 × 1020 cm−3) is achieved using C doping under B-rich conditions. Furthermore, bipolar doping is confirmed to be feasible in BP. An anneal temperature of at least 1000 °C is necessary for crystallization and dopant activation. Hole mobilities are low and indirect optical transitions are stronger than that predicted by theory. Low crystalline quality probably plays a role in both cases. High figures of merit for transparent conductors might be achievable in extrinsically doped BP films with improved crystalline quality.

Original languageAmerican English
Article number2200031
Number of pages11
JournalAdvanced Materials Interfaces
Issue number12
StatePublished - 2022

Bibliographical note

Publisher Copyright:
© 2022 The Authors. Advanced Materials Interfaces published by Wiley-VCH GmbH.

NREL Publication Number

  • NREL/JA-5K00-82405


  • bipolar doping
  • boron phosphide
  • p-type transparent conductors
  • phosphides
  • sputtering


Dive into the research topics of 'Boron Phosphide Films by Reactive Sputtering: Searching for a P-Type Transparent Conductor'. Together they form a unique fingerprint.

Cite this