Ultraviolet GaN photodetectors on Si via oxide buffer heterostructures with integrated short period oxide-based distributed Bragg reflectors and leakage suppressing metal-oxide-semiconductor contacts
- IHP, Im Technologiepark 25, 15236 Frankfurt (Oder) (Germany)
- Siltronic, Hanns-Seidel-Platz 4, 81737 München (Germany)
Based on a novel double step oxide buffer heterostructure approach for GaN integration on Si, we present an optimized Metal-Semiconductor-Metal (MSM)-based Ultraviolet (UV) GaN photodetector system with integrated short-period (oxide/Si) Distributed Bragg Reflector (DBR) and leakage suppressing Metal-Oxide-Semiconductor (MOS) electrode contacts. In terms of structural properties, it is demonstrated by in-situ reflection high energy electron diffraction and transmission electron microscopy-energy dispersive x-ray studies that the DBR heterostructure layers grow with high thickness homogeneity and sharp interface structures sufficient for UV applications; only minor Si diffusion into the Y{sub 2}O{sub 3} films is detected under the applied thermal growth budget. As revealed by comparative high resolution x-ray diffraction studies on GaN/oxide buffer/Si systems with and without DBR systems, the final GaN layer structure quality is not significantly influenced by the growth of the integrated DBR heterostructure. In terms of optoelectronic properties, it is demonstrated that—with respect to the basic GaN/oxide/Si system without DBR—the insertion of (a) the DBR heterostructures and (b) dark current suppressing MOS contacts enhances the photoresponsivity below the GaN band-gap related UV cut-off energy by almost up to two orders of magnitude. Given the in-situ oxide passivation capability of grown GaN surfaces and the one order of magnitude lower number of superlattice layers in case of higher refractive index contrast (oxide/Si) systems with respect to classical III-N DBR superlattices, virtual GaN substrates on Si via functional oxide buffer systems are thus a promising robust approach for future GaN-based UV detector technologies.
- OSTI ID:
- 22314322
- Journal Information:
- Journal of Applied Physics, Vol. 116, Issue 8; Other Information: (c) 2014 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA); ISSN 0021-8979
- Country of Publication:
- United States
- Language:
- English
Similar Records
Multicolour photodetector based on a ZnSe/ZnTe/GaAs heterostructure
Performance enhancement of GaN metal–semiconductor–metal ultraviolet photodetectors by insertion of ultrathin interfacial HfO{sub 2} layer
Related Subjects
71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
DIFFUSION
ELECTRON DIFFRACTION
FILMS
GALLIUM NITRIDES
LAYERS
LEAKS
PASSIVATION
PHOTODETECTORS
REFLECTION
REFRACTIVE INDEX
RESOLUTION
SEMICONDUCTOR MATERIALS
SUBSTRATES
SUPERLATTICES
THICKNESS
TRANSMISSION ELECTRON MICROSCOPY
ULTRAVIOLET RADIATION
X-RAY DIFFRACTION
YTTRIUM OXIDES