STRUCTURAL AND ELECTRICAL PROPERTIES OF RF MAGNETRON SPUTTERED TANTALUM OXIDE FILMS

2011 ◽  
Vol 10 (04n05) ◽  
pp. 749-753
Author(s):  
S. V. JAGADEESH CHANDRA ◽  
D. S. PARK ◽  
S. UTHANNA ◽  
CHEL-JONG CHOI ◽  
A. GURUVA REDDY

RF magnetron sputtering technique was employed for deposition of tantalum oxide films on p-type silicon substrates by sputtering of pure tantalum oxide target in the presence of oxygen and argon gases at a temperature of 303 K. X-ray photoelectron spectroscopic and X-ray diffraction studies indicated that the films annealed at 773 K were stoichiometric and polycrystalline respectively. The accumulation capacitance for the devices in a structure of Al/Ta2O5/p-Si has been decreased noticeably lower values for the devices annealed at high temperatures. Improved current–voltage characteristics were observed for all annealed devices with Poole–Frenkel conduction mechanism.

2015 ◽  
Vol 230 ◽  
pp. 205-210 ◽  
Author(s):  
K.A. Avramenko ◽  
Nina N. Roshchina ◽  
G.P. Olkhovik ◽  
Petro S. Smertenko ◽  
Lyudmyla V. Zavyalova

This paper reports on the ZnO film structures obtained by MOCVD method from acetylacetonate of zinc and diethyldithiocarbamate of zinc on silicon substrates at 280-320 оС substrate. The structural, emitting and transport properties of the ZnO films were examined by X-ray diffraction, Scanning electronic microscopy, Photoluminescent microscopy and Current-Voltage methods. The electrical transport mechanisms were analyzed on the base of differential and injection approaches. The ZnO/Si structure with ZnO film obtained was found to be appropriate for use in electronic devices due to their structural and electrical properties.


Author(s):  
A.E. Nikolaev ◽  
Yu.V. Melnik ◽  
M.N. Blashenkov ◽  
N.I. Kuznetsov ◽  
I.P. Nikitina ◽  
...  

Gallium nitride films were successfully grown by HVPE technique on p-type 6H-SiC substrate. The layers exhibit high crystal quality as was determined by X-ray diffraction. Photoluminescence (PL) of these films was measured. The PL spectra were dominated by band edge emission. Concentration Nd-Na in undoped epitaxial layers ranged from 2×1017 to 1×1019cm−3. Mesa-structures formed by reactive ion etching showed good rectifying current-voltage characteristics for GaN/SiC pn heterojunctions.


1991 ◽  
Vol 230 ◽  
Author(s):  
Kathleen R. Collen ◽  
Arthur B. Ellis ◽  
J. D. Busch ◽  
A. D. Johnson

AbstractThin films of the shape memory alloy NiTi have been sputter-deposited onto ptype silicon substrates. Films that are initially amorphous may be crystallized by vacuum annealing. The crystalline films exhibit the B2->B19′ phase change associated with the shape memory effect while remaining in contact with the silicon substrate. Transition temperatures were determined by resistance measurements and x-ray diffraction. The NiTi - Si contacts are diodes, as evidenced by their current-voltage characteristics; however, the effect of the phase change on the barrier height could not be determined.


2013 ◽  
Vol 1494 ◽  
pp. 77-82
Author(s):  
T. N. Oder ◽  
A. Smith ◽  
M. Freeman ◽  
M. McMaster ◽  
B. Cai ◽  
...  

ABSTRACTThin films of ZnO co-doped with lithium and phosphorus were deposited on sapphire substrates by RF magnetron sputtering. The films were sequentially deposited from ultra pure ZnO and Li3PO4 solid targets. Post deposition annealing was carried using a rapid thermal processor in O2 and N2 at temperatures ranging from 500 °C to 1000 °C for 3 min. Analyses performed using low temperature photoluminescence spectroscopy measurements reveal luminescence peaks at 3.359, 3.306, 3.245 eV for the co-doped samples. The x-ray diffraction 2θ-scans for all the films showed a single peak at about 34.4° with full width at half maximum of about 0.17°. Hall Effect measurements revealed conductivities that change from p-type to n-type over time.


2010 ◽  
Vol 25 (S1) ◽  
pp. S36-S39 ◽  
Author(s):  
Tieying Yang ◽  
Xiubo Qin ◽  
Huan-hua Wang ◽  
Quanjie Jia ◽  
Runsheng Yu ◽  
...  

Transparent p-type conducting Ga-doped SnO2 thin films were prepared using reactive rf-magnetron sputtering. Good p-type conduction was directly realized without the need of postdeposition annealing. The p-type conductivity was found to be very sensitive to the growth condition and process, suggesting that the carrier behavior is strongly related to the fine microstructure of the films. The microstructures of the films were characterized using synchrotron X-ray diffraction and specular reflectivity techniques. The valence state of the Ga dopant was measured from X-ray photoelectron spectra to explain the origin of net holes presented in the films.


2011 ◽  
Vol 287-290 ◽  
pp. 2140-2143 ◽  
Author(s):  
Jian Huang ◽  
Lin Jun Wang ◽  
Ke Tang ◽  
Ji Jun Zhang ◽  
Wei Min Shi ◽  
...  

ZnS films were prepared by radio-frequency (RF) magnetron sputtering method. The effects of substrate temperature and annealing treatment on the properties of ZnS films were studied. The ZnS films were characterized by X-ray diffraction (XRD), UV-visible spectrophotometer, and electrical measurements. The results showed that the higher substrate temperature and post-deposition annealing treatment was helpful in improving the crystalline quality of the films, and the film had an n-type conductivity. N-type ZnS films were also deposited on p-type single-crystalline silicon (Si) substrates to fabricate ZnS/ Si heterojunction. The current-voltage (I-V) characteristic of the heterojunction was examined, which showed a rectifying behavior with turn-on voltage of about 2V.


2017 ◽  
Vol 31 (25) ◽  
pp. 1745022 ◽  
Author(s):  
Yaping Qi ◽  
Xiangbo Liu ◽  
Hao Ni ◽  
Ming Zheng ◽  
Liping Chen ◽  
...  

La[Formula: see text]Hf[Formula: see text]MnO3 films were grown on 0.05 wt.% Nb-doped SrTiO3 substrates by pulsed laser deposition. X-ray diffraction measurements demonstrated that our samples were of good epitaxy and single-crystal. The temperature-dependent resistance has been investigated. It was observed that the as-grown film of La[Formula: see text]Hf[Formula: see text]MnO3 exhibited a typical paramagnetic-ferromagnetic transition. Heterojunctions of La[Formula: see text]Hf[Formula: see text]MnO3/0.05 wt.% Nb-doped SrTiO3 exhibited-asymmetric current–voltage characteristics and a remarkable temperature-dependent rectifying behavior in a wide temperature range (from 40 K to 300 K). And the most remarkable observation of this work is the existence of a crossover from positive to negative magnetoresistance in the La[Formula: see text]Hf[Formula: see text]MnO3/0.05 wt.% Nb-doped SrTiO3 heterojunction as the temperature decreases. A temperature-dependent magnetoresistance was studied as well. The rectifying characteristics and tunable magnetoresistance of these heterojunctions may be attributed to band structure of La[Formula: see text]Hf[Formula: see text]MnO3/0.05 wt.% Nb-doped SrTiO3 heterojunction.


2019 ◽  
Vol 11 (22) ◽  
pp. 8-13
Author(s):  
Mohammed A. Razooqi

A polycrystalline CdTefilms have been prepared by thermal evaporation technique on glass substrate at room temperature. The films thickness was about700±50 nm. Some of these films were annealed at 573 K for different duration times (60, 120 and 180 minutes), and other CdTe films followed by a layer of CdCl2 which has been deposited on them, and then the prepared CdTe films with CdCl2 layer have been annealed for the same conditions. The structures of CdTe films without and with CdCl2 layer have been investigated by X-ray diffraction. The as prepared and annealed films without and with CdCl2 layer were polycrystalline structure with preferred orientation at (111) plane. The better structural properties have been observed in presence of CdCl2 layer. The D.C conductivity for CdTe films with CdCl2 layershowed higher values. The electrical activation energy influenced with increasing duration times of annealing. Hall Effect measurement was indicated that all CdTe films are p-type. The carrier concentration, Hall mobility and the carrier life time wereaffected by increasing duration times of annealing.


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