Chemistry, microstructure, and electrical properties at interfaces between thin films of platinum and alpha (6H) silicon carbide (0001)

1995 ◽  
Vol 10 (9) ◽  
pp. 2336-2342 ◽  
Author(s):  
L.M. Porter ◽  
R.F. Davis ◽  
J.S. Bow ◽  
M.J. Kim ◽  
R.W. Carpenter

Thin films (4-1000 Å) of Pt were deposited via UHV electron beam evaporation at room temperature on monocrystalline, n-type α (6H)-SiC(0001) substrates and examined in terms of chemistry, microstructure, and electrical properties. The as-deposited contacts were polycrystalline and showed excellent rectifying behavior with low ideality factors (n < 1.1) and leakage currents of 5 × 10−8 A/cm2 at −10 V. The Schottky barrier height increased from 1.06 eV before annealing to 1.26 eV after successive 20 min anneals at 450, 550, 650, and 750 °C. In addition, the leakage currents decreased to 2 × 10−8 A/cm2 at −10 V. Interfacial reactions were not observed at annealing temperatures below 750 °C; above this temperature, Pt2Si and C precipitates were identified in the reaction zone.

1995 ◽  
Vol 10 (1) ◽  
pp. 26-33 ◽  
Author(s):  
L.M. Porter ◽  
R.F. Davis ◽  
J.S. Bow ◽  
M.J. Kim ◽  
R.W. Carpenter

Thin films (4–1000 Å) of Co were deposited onto n-type 6H-SiC(0001) wafers by UHV electron beam evaporation. The chemistry, microstructure, and electrical properties were determined using x-ray photoelectron spectroscopy, high resolution transmission electron microscopy, and I-V and C-V measurements, respectively. The as-deposited contacts exhibited excellent rectifying behavior with low ideality factors and leakage currents of n < 1.06 and 2.0 × 10−8 A/cm2 at −10 V, respectively. During annealing at 1000 °C for 2 min, significant reaction occurred resulting in the formation of CoSi and graphite. These annealed contacts exhibited ohmic-like character, which is believed to be due to defects created in the interface region.


2017 ◽  
Vol 25 (2) ◽  
pp. 243-250
Author(s):  
Nguyen Nang Dinh ◽  
Le Dinh Trong ◽  
Pham Duy Long

Bulk nanostructured perovskites of La0.67-xLi3xTiO3 (LLTO) were prepared by using thermally ball-grinding from compounds of La2O3, Li2CO3 and TiO2. From XRD analysis, it was found that LTTO materials were crystallized with nano-size grains of an average size of 30 nm. The bulk ionic conductivity was found strongly dependent on the Li+ composition, the samples with x = 0.11 (corresponding to a La0.56Li0.33TiO3 compound) have the best ionic conductivity, which is ca. 3.2 x 10-3 S/cm at room temperature. The LLTO amorphous films were made by electron beam deposition. At room temperature the smooth films have ionic conductivity of 3.5 x 10-5  S/cm and transmittance of 80%. The optical bandgap of the films was found to be of 2.3 eV. The results have shown that the perovskite La0.56Li0.33TiO3  thin films can be used for a transparent solid electrolyte in ionic battery and in all-solid-state electrochromic devices, in particular.    


2019 ◽  
Vol 14 (29) ◽  
pp. 37-43 ◽  
Author(s):  
Raied K. Jamal

The electrical properties of pure NiO and NiO:Au Films which aredeposited on glass substrate with various dopant concentrations(1wt.%, 2wt%, 3wt.% and 4wt.%) at room temperature 450 Coannealing temperature will be presented. The results of the hall effectshowed that all the films were p-type. The Hall mobility decreaseswhile both carrier concentration and conductivity increases with theincreasing of annealing temperatures and doping percentage, Thus,indicating the behavior of semiconductor, and also the D.Cconductivity from which the activation energy decrease with thedoping concentration increase and transport mechanism of the chargecarriers can be estimated.


1995 ◽  
Vol 10 (3) ◽  
pp. 668-679 ◽  
Author(s):  
L.M. Porter ◽  
R.F. Davis ◽  
J.S. Bow ◽  
M.J. Kim ◽  
R.W. Carpenter ◽  
...  

Epitaxial thin films (4–1000 Å) of Ti contacts have been deposited via UHV electron beam evaporation at room temperature on monocrystalline, n-type, alpha (6H)-SiC(0001). The interfacial chemistry and microstructure, and the electrical properties, were investigated at room temperature and after annealing at 700 °C up to 60 min. High resolution TEM analyses revealed the formation during annealing of reaction zones consisting of Ti5Si3 and TiC. The corresponding electrical properties exhibited considerable stability except after an initial 20 min anneal. Current-voltage (I-V) measurements showed that the Ti contacts were rectifying with low ideality factors (n < 1.09) and typical leakage currents of 5 × 10−7 A/cm2 at −10 V. The Schottky barrier heights calculated from x-ray photoelectron spectroscopy and I-V and V-V measurements were between 0.79 and 0.88 eV for the as-deposited contacts and between 0.86 and 1.04 eV for the annealed contacts.


2015 ◽  
Vol 15 (9) ◽  
pp. 964-969 ◽  
Author(s):  
Hui Kyung Park ◽  
Jaeseung Jo ◽  
Hee Kyeung Hong ◽  
Gwang Yeom Song ◽  
Jaeyeong Heo

Vacuum ◽  
2007 ◽  
Vol 81 (9) ◽  
pp. 1023-1028 ◽  
Author(s):  
Jianke Yao ◽  
Jianda Shao ◽  
Hongbo He ◽  
Zhengxiu Fan

2013 ◽  
Vol 2013 ◽  
pp. 1-5 ◽  
Author(s):  
H. Abdullah ◽  
S. Habibi

CuInSe2(CIS) thin films are successfully prepared by electron beam evaporation. Pure Cu, In, and Se powders were mixed and ground in a grinder and made into a pellet. The pallets were deposited via electron beam evaporation on FTO substrates and were varied by varying the annealing temperatures, at room temperature, 250°C, 300°C, and 350°C. Samples were analysed by X-ray diffractometry (XRD) for crystallinity and field-emission scanning electron microscopy (FESEM) for grain size and thickness. I-V measurements were used to measure the efficiency of the CuInSe2/ZnS solar cells. XRD results show that the crystallinity of the films improved as the temperature was increased. The temperature dependence of crystallinity indicates polycrystalline behaviour in the CuInSe2films with (1 1 1), (2 2 0)/(2 0 4), and (3 1 2)/(1 1 6) planes at 27°, 45°, and 53°, respectively. FESEM images show the homogeneity of the CuInSe2formed. I-V measurements indicated that higher annealing temperatures increase the efficiency of CuInSe2solar cells from approximately 0.99% for the as-deposited films to 1.12% for the annealed films. Hence, we can conclude that the overall cell performance is strongly dependent on the annealing temperature.


1975 ◽  
Vol 30 (12) ◽  
pp. 1661-1666 ◽  
Author(s):  
P. J. P. De Maayer ◽  
J. D. Mackenzie

Abstract Thin films of metallically conductive titanium mononitride and carbide were prepared by means of electron beam evaporation. The composition of the samples could be changed over appreciable ranges by introducing nitrogen in the system or adding carbon to the pure starting material, respectively. The transport properties of the resulting compounds were studied as a function of nonstoichiometry and defect structure. A plausible explanation for the different behavior of the films compared to corresponding bulk samples is given and a correlation between the change in electron concentration and the electron transfer theory is presented.


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