Flexible metal-semiconductor-metal device prototype on wafer-scale thick boron nitride layers grown by MOVPE

Abstract

Practical boron nitride (BN) detector applications will require uniform materials over large surface area and thick BN layers. To report important progress toward these technological requirements, 1~2.5 µm-thick BN layers were grown on 2-inch sapphire substrates by metal-organic vapor phase epitaxy (MOVPE). The structural and optical properties were carefully characterized and discussed. The thick layers exhibited strong band-edge absorption near 215 nm. A highly oriented two-dimensional h-BN structure was formed at the film/sapphire interface, which permitted an effective exfoliation of the thick BN film onto other adhesive supports. And this structure resulted in a metal-semiconductor-metal (MSM) device prototype fabricated on BN membrane delaminating from the substrate. MSM photodiode prototype showed low dark current of 2 nA under 100 V, and 100 ± 20% photoconductivity yield for deep UV light illumination. These wafer-scale MOVPE-grown thick BN layers present great potential for the development of deep UV photodetection applications, and even for flexible (opto-) electronics in the future.

Quantitative Characterization of Structural and Mechanical Properties of Boron Nitride Nanotubes in High Temperature Environments

“…The recorded Raman spectra represent the structural characteristics of the B-N bonds in the thermally heated BNNTs that underwent little or no oxidation. At room temperature, BNNTs possess a G band ( E 2 g mode) peak at 1369 cm −1 29 – 31 . The G band peak is found to downshift to about 1339 cm −1 at 900 °C, indicating a redshift change of 30 cm −1 in wavelength as a result of a temperature increase of about 875 °C.…”

Synthesis of boron nitride nanotubes using an oxygen and carbon dual-free precursor

“…3(a)). 35,36 It is interesting to note that no other signicant peaks (especially at around 1580 cm À1 belonging to carbon) 37,38 are detected, which further conrms the high purity of the as grown BNNTs. The FTIR spectra in Fig.…”

Optical properties of GaN nanowires grown on chemical vapor deposited-graphene

“…Following these promising predictions, the growth of GaN thin films on layered materials such as graphene 5 or h-BN [6][7][8][9] is today actively explored. In particular, GaN film growth and mechanical peel-off was demonstrated leading to spectacular demonstrations of LEDs 5,6 , HEMTs by mechanical transfer 7,9 or metal-semiconductor-metal photodiodes 10 . However, the expected reduction of defect density in thin films was not achieved: a dislocation density around 10 9 -10 10 cm -2 was observed [5][6][7]9,10 .…”

“…In particular, GaN film growth and mechanical peel-off was demonstrated leading to spectacular demonstrations of LEDs 5,6 , HEMTs by mechanical transfer 7,9 or metal-semiconductor-metal photodiodes 10 . However, the expected reduction of defect density in thin films was not achieved: a dislocation density around 10 9 -10 10 cm -2 was observed [5][6][7]9,10 . The interest has then turned to the growth of nanowires (NWs) on 2D materials since these nano-objects are known to be free from threading dislocations even on highly lattice-mismatched substrates.…”