Schottky barriers on anisotropic semiconductor GaTe

Bose, D. N.; Pal, Snehanshu

doi:10.1080/13642819708202319

Cited by 19 publications

(13 citation statements)

References 10 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…With no illumination and drain bias voltage, the device is in its equilibrium state, characterized by Schottky barriers at the contacts. Considering GaSe as a p-type material with Fermi energy of around 5.6 eV, which is larger than the Au work function 28 , we plotted the schematic band diagram of the devices ( Fig. 3a,b ).…”

Section: Resultsmentioning

confidence: 99%

Strong enhancement of photoresponsivity with shrinking the electrodes spacing in few layer GaSe photodetectors

Cao

Cai

et al. 2015

Sci Rep

114

View full text Add to dashboard Cite

A critical challenge for the integration of optoelectronics is that photodetectors have relatively poor sensitivities at the nanometer scale. Generally, a large electrodes spacing in photodetectors is required to absorb sufficient light to maintain high photoresponsivity and reduce the dark current. However, this will limit the optoelectronic integration density. Through spatially resolved photocurrent investigation, we find that the photocurrent in metal-semiconductor-metal (MSM) photodetectors based on layered GaSe is mainly generated from the region close to the metal-GaSe interface with higher electrical potential. The photoresponsivity monotonically increases with shrinking the spacing distance before the direct tunneling happens, which was significantly enhanced up to 5,000 AW−1 for the bottom Ti/Au contacted device. It is more than 1,700-fold improvement over the previously reported results. The response time of the Ti/Au contacted devices is about 10–20 ms and reduced down to 270 μs for the devices with single layer graphene as metallic electrodes. A theoretical model has been developed to well explain the photoresponsivity for these two types of device configurations. Our findings realize reducing the size and improving the performance of 2D semiconductor based MSM photodetectors simultaneously, which could pave the way for future high density integration of optoelectronics with high performances.

show abstract

Section: Resultsmentioning

confidence: 99%

Strong enhancement of photoresponsivity with shrinking the electrodes spacing in few layer GaSe photodetectors

Cao

Cai

et al. 2015

Sci Rep

114

View full text Add to dashboard Cite

show abstract

“…[1][2][3][4][5][6][7][8][9][10][11][12] The band-gap energy of GaTe at room temperature is around 1.7 eV. This value is ideal for room-temperature x-ray and gamma-ray radiation detector applications.…”

Section: Introductionmentioning

confidence: 94%

“…Free-exciton, boundexciton, and edge emissions of undoped GaTe crystal have been well investigated, [7][8][9][10][11][12] and a shallow acceptor level around 0.15 eV has been reported and identified to be gallium vacancy V Ga . Undoped GaTe Schottky diodes were fabricated and tested, [3][4][5][6] and one DLTS measurement conducted at room temperature and above was reported. 4 GaTe crystal has a monoclinic structure with space group C2 / m, 7 while the well-studied GaSe crystal has a hexagonal structure with space group P62m; it is interesting to study the defects of GaTe in comparison with those of GaSe.…”

Section: Introductionmentioning

confidence: 99%

Deep levels in GaTe and GaTe:In crystals investigated by deep-level transient spectroscopy and photoluminescence

Cui

Caudel

Bhattacharya

et al. 2009

Journal of Applied Physics

View full text Add to dashboard Cite

Deep levels of undoped GaTe and indium-doped GaTe crystals are reported for samples grown by the vertical Bridgman technique. Schottky diodes of GaTe and GaTe:In have been fabricated and characterized using current-voltage, capacitance-voltage, and deep-level transient spectroscopy ͑DLTS͒. Three deep levels at 0.40, 0.59, and 0.67 eV above the valence band were found in undoped GaTe crystals. The level at 0.40 eV is associated with the complex consisting of gallium vacancy and gallium interstitial ͑V Ga -Ga i ͒, the level at 0.59 eV is identified as the tellurium-on-gallium antisite ͑Te Ga ͒, and the last one is tentatively assigned to be the doubly ionized gallium vacancy ͑V Ga ‫ء‬ ͒. Indium isoelectronic doping is found to have noticeable impacts on reducing the Schottky saturation current and suppressing the densities of Te Ga and V Ga ‫ء‬ defects. The peak which dominated the DLTS spectrum of GaTe:In is assigned to be the defect complex consisting of V Ga and indium interstitial ͑In i ͒. Low-temperature photoluminescence ͑PL͒ spectroscopy measurements were performed on GaTe and GaTe:In crystals. A shallow acceptor level at 140 meV corresponding to V Ga was measured in undoped GaTe. Two shallow acceptor levels at 123 and 74 meV corresponding to V Ga and indium-on-gallium antisite In Ga were observed in GaTe:In samples. The PL results suggested that the indium atoms could occupy gallium vacant sites during GaTe crystal growth period and thereby change the electrical and optical properties of GaTe crystal.

show abstract

“…GaTe is a relatively known semiconductor compound [21][22][23][27][28][29][30][31][32][33][34][35][36][37][38][39][40][41]45,47] and exist successful but limited Schottky contact studies [21][22][23][37][38][39][40] made using GaTe. GaTe belongs to the III-VI group in the periodic table and has a layered nature.…”

Section: Introductionmentioning

confidence: 99%