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Title: Structural and Electrical Characterization of 2” Ammonothermal Free-Standing GaN Wafers. Progress toward Pilot Production

Journal Article · · Materials
DOI:https://doi.org/10.3390/ma12121925· OSTI ID:1526335

Free-standing gallium nitride (GaN) substrates are in high demand for power devices, laser diodes, and high-power light emitting diodes (LEDs). SixPoint Materials Inc. has begun producing 2” GaN substrates through our proprietary Near Equilibrium AmmonoThermal (NEAT) growth technology. In a single 90 day growth, eleven c-plane GaN boules were grown from free-standing hydride vapor phase epitaxy (HVPE) GaN substrates. The boules had an average X-ray rocking curve full width at half maximum (FWHM) of 33 ± 4 in the 002 reflection and 44 ± 6 in the 201 reflection using 0.3 mm divergence slits. The boules had an average radius of curvature of 10.16 ± 3.63 m. The quality of the boules was highly correlated to the quality of the seeds. A PIN diode grown at Georgia Tech on a NEAT GaN substrate had an ideality factor of 2.08, a high breakdown voltage of 1430 V, and Baliga’s Figure of Merit of >9.2 GW/cm2. These initial results demonstrate the suitability of using NEAT GaN substrates for high-quality MOCVD growth and fabrication of high-power vertical GaN switching devices.

Research Organization:
SixPoint Materials, Inc., Buellton, CA (United States)
Sponsoring Organization:
USDOE Advanced Research Projects Agency - Energy (ARPA-E)
Grant/Contract Number:
AR0000445; SC0013791
OSTI ID:
1526335
Alternate ID(s):
OSTI ID: 1613599
Journal Information:
Materials, Journal Name: Materials Vol. 12 Journal Issue: 12; ISSN 1996-1944
Publisher:
MDPICopyright Statement
Country of Publication:
Switzerland
Language:
English
Citation Metrics:
Cited by: 12 works
Citation information provided by
Web of Science

References (20)

1.1-kV Vertical GaN p-n Diodes With p-GaN Regrown by Molecular Beam Epitaxy journal August 2017
5.0 kV breakdown-voltage vertical GaN p–n junction diodes journal February 2018
High Voltage Vertical GaN p-n Diodes With Avalanche Capability journal October 2013
High-Breakdown-Voltage and Low-Specific-on-Resistance GaN p–n Junction Diodes on Free-Standing GaN Substrates Fabricated Through Low-Damage Field-Plate Process journal February 2013
Let There Be Light-With Gallium Nitride: The 2014 Nobel Prize in Physics journal November 2014
Vertical GaN merged PiN Schottky diode with a breakdown voltage of 2 kV journal May 2017
The role of threading dislocations in the physical properties of GaN and its alloys journal December 1999
Correlation between nanopipes formed from screw dislocations during homoepitaxial growth by metal-organic vapor-phase epitaxy and reverse leakage current in vertical p–n diodes on a free-standing GaN substrates journal May 2019
Free electron concentration dependent sub-bandgap optical absorption characterization of bulk GaN crystals journal December 2015
Vertical Power p-n Diodes Based on Bulk GaN journal February 2015
Gallium nitride vertical power devices on foreign substrates: a review and outlook journal June 2018
X-ray characterization technique for the assessment of surface damage in GaN wafers journal November 2018
Bulk GaN flip-chip violet light-emitting diodes with optimized efficiency for high-power operation journal January 2015
Modeling of threading dislocation reduction in growing GaN layers journal October 2001
Excellent crystallinity of truly bulk ammonothermal GaN journal August 2008
Curvature and bow of bulk GaN substrates journal July 2016
Development of GaN wafers via the ammonothermal method journal October 2014
Reduction of crack density in ammonothermal bulk GaN growth journal December 2016
Wet etching of GaN, AlN, and SiC: a review journal January 2005
1.7-kV and 0.55-$\text{m}\Omega \cdot \text {cm}^{2}$ GaN p-n Diodes on Bulk GaN Substrates With Avalanche Capability journal February 2016