Characterization and Modeling of Photoconductive GaN Ultraviolet Detectors
- 1 January 1997
- journal article
- Published by Springer Nature in MRS Internet Journal of Nitride Semiconductor Research
Abstract
In this work high gain GaN photoconductive UV detectors have been fabricated and characterized, and a novel gain mechanism, dominant in these detectors, is described. DC responsivities higher than 103A/W have been measured for an incident power of lW/m2 at room temperature. The photoconductive gain depends directly on the bias voltage and scales with incident power as P−k (k ≈ 0.9) for more than five decades. A decrease of both gain and k parameter with temperature has also been observed. As a consequence of the slow non-exponential transient response, AC gain measurements result in lower values for gain and k parameter, which are frequency dependent. The high responsivity, non-linear behavior and slow non-exponential transient response, are all modeled taking into account a modulation mechanism of the layer conductive volume. Such spatial modulation is due to the photovoltaic response of the potential barriers related to the surface and charged dislocations arrays.Keywords
This publication has 14 references indexed in Scilit:
- Deep levels and persistent photoconductivity in GaN thin filmsApplied Physics Letters, 1997
- Al x Ga 1−x N (0⩽x⩽1) ultraviolet photodetectors grown on sapphire by metal-organic chemical-vapor depositionApplied Physics Letters, 1997
- High quality GaN grown by MOVPEJournal of Crystal Growth, 1997
- Photocurrent decay in n-type GaN thin filmsApplied Physics Letters, 1996
- Mechanisms of recombination in GaN photodetectorsApplied Physics Letters, 1996
- High responsitivity intrinsic photoconductors based on AlxGa1−xNApplied Physics Letters, 1996
- Semiconductor ultraviolet detectorsJournal of Applied Physics, 1996
- Yellow Band and Deep levels in Undoped MOVPE GaN.MRS Internet Journal of Nitride Semiconductor Research, 1996
- Kinetics of photoconductivity in n-type GaN photodetectorApplied Physics Letters, 1995
- Photoconductive ultraviolet sensor using Mg-doped GaN on Si(111)Applied Physics Letters, 1995