Understanding and control of bipolar self-doping in copper nitride

Journal Article · Sat May 14 00:00:00 EDT 2016 · Journal of Applied Physics

DOI:https://doi.org/10.1063/1.4948244· OSTI ID:22596956

Tamboli, Adele C.; Caskey, Christopher M.; Toberer, Eric S. ^[1]; Schwartz, Craig P.; Nordlund, Dennis ^[2]; Vinson, John ^[3]; Prendergast, David ^[4]; Tuomisto, Filip; Linez, Florence ^[5]; Christensen, Steven T.; Lany, Stephan; Zakutayev, Andriy ^[1]

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1. National Renewable Energy Laboratory, Golden, Colorado 80401 (United States)
2. SLAC National Accelerator Lab, Menlo Park, California 94720 (United States)
3. National Institute of Standards and Technology, Gaithersburg, Maryland 20899 (United States)
4. Lawrence Berkeley National Laboratory, Berkeley, California 94720 (United States)
5. Aalto University, Espoo 02150 (Finland)

Semiconductor materials that can be doped both n-type and p-type are desirable for diode-based applications and transistor technology. Copper nitride (Cu{sub 3}N) is a metastable semiconductor with a solar-relevant bandgap that has been reported to exhibit bipolar doping behavior. However, deeper understanding and better control of the mechanism behind this behavior in Cu{sub 3}N is currently lacking in the literature. In this work, we use combinatorial growth with a temperature gradient to demonstrate both conduction types of phase-pure, sputter-deposited Cu{sub 3}N thin films. Room temperature Hall effect and Seebeck effect measurements show n-type Cu{sub 3}N with 10{sup 17} electrons/cm{sup 3} for low growth temperature (≈35 °C) and p-type with 10{sup 15} holes/cm{sup 3}–10{sup 16} holes/cm{sup 3} for elevated growth temperatures (50 °C–120 °C). Mobility for both types of Cu{sub 3}N was ≈0.1 cm{sup 2}/Vs–1 cm{sup 2}/Vs. Additionally, temperature-dependent Hall effect measurements indicate that ionized defects are an important scattering mechanism in p-type films. By combining X-ray absorption spectroscopy and first-principles defect theory, we determined that V{sub Cu} defects form preferentially in p-type Cu{sub 3}N, while Cu{sub i} defects form preferentially in n-type Cu{sub 3}N, suggesting that Cu{sub 3}N is a compensated semiconductor with conductivity type resulting from a balance between donor and acceptor defects. Based on these theoretical and experimental results, we propose a kinetic defect formation mechanism for bipolar doping in Cu{sub 3}N that is also supported by positron annihilation experiments. Overall, the results of this work highlight the importance of kinetic processes in the defect physics of metastable materials and provide a framework that can be applied when considering the properties of such materials in general.

• OSTI ID: 22596956
• Journal Information: Journal of Applied Physics, Vol. 119, Issue 18; Other Information: (c) 2016 Author(s); Country of input: International Atomic Energy Agency (IAEA); ISSN 0021-8979
• Country of Publication: United States
• Language: English

Related Subjects

71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
ABSORPTION
ABSORPTION SPECTROSCOPY
ANNIHILATION
COPPER
COPPER NITRIDES
DEFECTS
DOPED MATERIALS
ELECTRONS
HALL EFFECT
HOLES
POSITRONS
P-TYPE CONDUCTORS
SEEBECK EFFECT
TEMPERATURE DEPENDENCE
TEMPERATURE GRADIENTS
TEMPERATURE RANGE 0273-0400 K
THIN FILMS
TRANSISTORS
X RADIATION
X-RAY SPECTROSCOPY