High responsivity A-plane GaN-based metal-semiconductor-metal photodetectors for polarization-sensitive applications
APPLIED PHYSICS LETTERS, cilt.94, sa.21, 2009 (SCI-Expanded, Scopus)
- Yayın Türü: Makale / Tam Makale
- Cilt numarası: 94 Sayı: 21
- Basım Tarihi: 2009
- Doi Numarası: 10.1063/1.3143230
- Dergi Adı: APPLIED PHYSICS LETTERS
- Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus
- Anahtar Kelimeler: current density, electrical resistivity, energy gap, gallium compounds, III-V semiconductors, metal-semiconductor-metal structures, photodetectors, polarisation, sapphire, wide band gap semiconductors, ULTRAVIOLET DETECTORS
- Orta Doğu Teknik Üniversitesi Adresli: Hayır
Özet
The fabrication and characterization of metal-semiconductor-metal polarization-sensitive photodetectors based on A-plane GaN grown on R-plane sapphire substrates is reported. These photodetectors take advantage of the in-plane crystal anisotropy, which results in linear dichroism near the band gap energy. The high resistivity of the A-plane GaN material leads to extremely low dark currents. For an optimized finger spacing of 1 mu m, dark current density and responsivity at 30 V are 0.3 nA/mm(2) and 2 A/W, respectively. A maximum polarization sensitivity ratio of 1.8 was determined. In a differential configuration, the full width at half maximum of the polarization-sensitive region is 8.5 nm.