Sputter synthesis of wafer-scale hexagonal boron nitride films via interface segregation

Jitsuo Ohta,Hiroshi Fujioka

doi:10.1063/1.4995652

Abstract

We demonstrated the crystal growth of wafer-scale hexagonal boron nitride (hBN) films on AlN template substrates by pulsed sputtering deposition using Fe catalysts. It was found that hBN films with high crystalline quality were formed at the hetero-interfaces between the Fe catalytic layers and the AlN templates. The full width at half maximum value of the E2g Raman spectrum for the hBN film was as small as 5.1 cm−1. The hBN film showed a highly c-axis-oriented structure and a strong near-band-edge deep ultraviolet emission at room temperature. The present results indicate that the sputter synthesis of hBN films via interface segregation opens a new pathway for the wafer-scale production of high-quality hBN films, and we envisage its potential applications in the fabrication of prospective hBN-based optoelectronic devices.

Highlights

Hexagonal boron nitride has recently gained considerable attention because of its outstanding properties such as its wide bandgap, high thermal and chemical stability, and two-dimensional layered structure
In the chemical vapor deposition (CVD) growth of Hexagonal boron nitride (hBN) films, transition metals such as Cu, Ni, or Fe are usually used as catalysts in the form of a foil or an interlayer to promote the formation of the hBN films via surface reaction and/or segregation of the dissolved B and N atoms from the metal.[13,14,15]
We have found that using a new growth technique called pulsed sputtering deposition (PSD) allows producing device-quality group III nitride semiconductor films with a high growth rate, aElectronic mail: johta@iis.u-tokyo.ac.jp 2166-532X/2017/5(7)/076107/5

Summary

Introduction

Hexagonal boron nitride (hBN) has recently gained considerable attention because of its outstanding properties such as its wide bandgap (approximately 6.0 eV), high thermal and chemical stability, and two-dimensional layered structure. Jitsuo Ohta1,2,a and Hiroshi Fujioka1,3 1Institute of Industrial Science, The University of Tokyo, 4-6-1 Komaba, Tokyo 153-8505, Japan 2PRESTO, Japan Science and Technology Agency, 4-1-8 Honcho, Kawaguchi, Saitama 332-0012, Japan 3ACCEL, Japan Science and Technology Agency, 5 Sanbancho, Chiyoda-ku, Tokyo 102–0075, Japan (Received 14 May 2017; accepted 11 July 2017; published online 21 July 2017)

Results

Conclusion