Preliminary demonstration of diamond-GaN <i>p–n</i> diodes via grafting

J Jie Zhou Y Yi Lu C Chenyu Wang L Luke Suter (Fraunhofer USA Inc., Center Midwest 4 , East Lansing, Michigan 48824,) A Aaron Hardy (Fraunhofer USA Inc., Center Midwest 4 , East Lansing, Michigan 48824,) T Tien Khee Ng (Photonics Laboratory, Division of Computer, Electrical, and Mathematical Sciences and Engineering) K Kai Sun Y Yifu Guo (College of Physics, Qingdao University 1 , Qingdao 266071,) Y Yang Liu T Tsung-Han Tsai (Department of Electrical and Computer Engineering, University of Wisconsin-Madison 1 , Madison, Wisconsin 53706,) X Xuanyu Zhou C Connor S. Bailey (Northrop Grumman Corporation 8 , Redondo Beach, California 90278,) M Michael Eller (Northrop Grumman Corporation 8 , Redondo Beach, California 90278,) S Stephanie Liu (Northrop Grumman Corporation 8 , Redondo Beach, California 90278,) Z Zetian Mi B Boon S. Ooi (Photonics Laboratory, Division of Computer, Electrical, and Mathematical Sciences and Engineering) M Matthias Muehle (Fraunhofer USA Inc., Center Midwest 4 , East Lansing, Michigan 48824,) K Katherine Fountaine (Northrop Grumman Corporation 8 , Redondo Beach, California 90278,) V Vincent Gambin (Northrop Grumman Corporation 8 , Redondo Beach, California 90278,) J Jung-Hun Seo (Department of Materials Design and Innovation, University at Buffalo, The State University of New York 3 , Buffalo, New York 14260,) Z Zhenqiang Ma

Abstract

Ultrawide bandgap (UWBG) semiconductors exhibit exceptional electrical and thermal properties, offering strong potential for high-power and high-frequency electronics. However, efficient doping in UWBG materials is typically limited to either n-type or p-type, constraining their application to unipolar devices. The realization of p–n junctions through heterogeneous integration of complementary UWBG (or WBG) semiconductors is hindered by lattice mismatch and thermal expansion differences. Here, we report the preliminary demonstration of diamond–GaN heterojunction p–n diodes fabricated via Grafting. A single-crystalline p+ diamond nanomembrane was integrated onto an epitaxially grown c-plane n−/n+ GaN substrate with an ultrathin ALD–Al2O3 interlayer. The resulting diodes exhibit an ideality factor of 1.55 and a rectification ratio of ∼104. Structural and interfacial properties were examined by AFM, XRD, Raman, and STEM, providing critical insights to guide further optimization of diamond–GaN p–n heterojunction devices.

Article Details

Volume / Issue Vol. 128, Issue 18
Published May 04, 2026
ISSN 0003-6951
Publisher American Institute of Physics

Journal Info

Applied Physics Letters

American Institute of Physics

ISSN: 0003-6951 Physical Sciences

Authors (21)

J

Jie Zhou

Y

Yi Lu

C

Chenyu Wang

L

Luke Suter

Fraunhofer USA Inc., Center Midwest 4 , East Lansing, Michigan 48824,

A

Aaron Hardy

Fraunhofer USA Inc., Center Midwest 4 , East Lansing, Michigan 48824,

T

Tien Khee Ng

Photonics Laboratory, Division of Computer, Electrical, and Mathematical Sciences and Engineering

K

Kai Sun

Y

Yifu Guo

College of Physics, Qingdao University 1 , Qingdao 266071,

Y

Yang Liu

T

Tsung-Han Tsai

Department of Electrical and Computer Engineering, University of Wisconsin-Madison 1 , Madison, Wisconsin 53706,

X

Xuanyu Zhou

C

Connor S. Bailey

Northrop Grumman Corporation 8 , Redondo Beach, California 90278,

M

Michael Eller

Northrop Grumman Corporation 8 , Redondo Beach, California 90278,

S

Stephanie Liu

Northrop Grumman Corporation 8 , Redondo Beach, California 90278,

Z

Zetian Mi

B

Boon S. Ooi

Photonics Laboratory, Division of Computer, Electrical, and Mathematical Sciences and Engineering

M

Matthias Muehle

Fraunhofer USA Inc., Center Midwest 4 , East Lansing, Michigan 48824,

K

Katherine Fountaine

Northrop Grumman Corporation 8 , Redondo Beach, California 90278,

V

Vincent Gambin

Northrop Grumman Corporation 8 , Redondo Beach, California 90278,

J

Jung-Hun Seo

Department of Materials Design and Innovation, University at Buffalo, The State University of New York 3 , Buffalo, New York 14260,

Z

Zhenqiang Ma