Transport Properties of Polycrystalline SiGe Thin Films Grown on SiO2

2004 ◽  
Vol 829 ◽  
Author(s):  
Minoru Mitsui ◽  
Keisuke Arimoto ◽  
Junji Yamanaka ◽  
Kiyokazu Nakagawa ◽  
Kentarou Sawano ◽  
...  

ABSTRACTTransport properties of polycrystalline Si1−xGex (x = 0, 30, 50 and 70) thin films on SiO2 were studied by Hall measurements and transport properties of the TFTs fabricated on the films were characterized. Si1−xGex films were p-type in spite of non-doping. Room temperature hole densities of Si1−xGex films increased from 5 × 1013 to 5 × 1016 cm−3 as Ge concentration increased from 30 % to 70 %. The acceptor levels in Si1−xGex were located at 0.43, 0.40 and 0.34 eV for x=0.3, 0.5 and 0.7 from valence band, respectively. The high leakage current of SiGe-TFTs was observed and drain current could not be turned off even when the high gate voltage was applied. The acceptor density increased with increasing annealing temperature from 700 °C to 800 °C. The leakage currents were independent of the annealing temperature and is thought to originate from Ge-related defects in grain boundaries.

1985 ◽  
Vol 52 ◽  
Author(s):  
J. A. Edmond ◽  
H. J. Kim ◽  
R. F. Davis

ABSTRACTIon implantation of 27Al+ and 31p+ ions into monocrystalline s-SiC films was conducted in order to acquire p-type and n-type conducting layers, respectively. Implant energies ranging from 110 to 190 keV and fluences from 7 × 1013 to 9 × 1014 cm-2 were used. In order to activate each dopant specie, rapid thermal annealing (RTA) was employed. A decrease in sheet resistance with increasing annealing temperature for both type layers was observed up to 1800°C. After annealing at this highest temperature for 300 s in 1 atm. Ar, the percent of activated and ionized n-type and p-type dopant was ≅20% and ≅0.5%, respectively, as determined by room temperature capacitance-voltage measurements. Recrystallization of both heavily damaged and amorphized layers occurred as a result of the use of the aforementioned annealing process. Unlike SPE regrowth in other compound semiconductors, no microtwins were present in the regrown bulk as observed by XTEM. SIMS analyses also showed that there was essentially no redistribution of P and moderate redistribution of Al from the corresponding as-implanted profiles after annealing.


2012 ◽  
Vol 501 ◽  
pp. 236-241 ◽  
Author(s):  
Ftema W. Aldbea ◽  
Noor Bahyah Ibrahim ◽  
Mustafa Hj. Abdullah ◽  
Ramadan E. Shaiboub

Thin films nanoparticles TbxY3-xFe5O12 (x=0.0, 1.0, 2.0) were prepared by the sol-gel process followed by annealing process at various annealing temperatures of 700° C, 800° C and 900° C in air for 2 h. The results obtained from X-ray diffractometer (XRD) show that the films annealed below 900°C exhibit peaks of garnet mixed with small amounts of YFeO3 and Fe2O3. Pure garnet phase has been detected in the films annealed at 900°C. Before annealing the films show amorphous structures. The particles sizes measurement using the field emission scanning electron microscope (FE-SEM) showed that the particles sizes increased as the annealing temperature increased. The magnetic properties were measured at room temperature using the vibrating sample magnetometer (VSM). The saturation magnetization (Ms) of the films also increased with the annealing temperature. However, different behavior of coercivity (Hc) has been observed as the annealing temperature was increased.


1999 ◽  
Vol 606 ◽  
Author(s):  
S. Bhaskar ◽  
S. B. Majumder ◽  
P. S. Dobal ◽  
R. S. Katiyar ◽  
A. L. M. Cruz ◽  
...  

AbstractIn the present work we have optimized the process parameters to yield homogeneous, smooth ruthenium oxide (RuO2) thin films on silicon substrates by a solution deposition technique using RuCl3.×.H2O as the precursor material. Films were annealed in a temperature range of 300°C to 700°C, and it was found that RuO2 crystallizes at a temperature as low as 400°C. The crystallinity of the films improves with increased annealing temperature and the resistivity decreases from 4.86µΩ-m (films annealed at 400°C) to 2.94pµΩ (films annealed at 700°C). Ageing of the precursor solution has a pronounced effect on the measured resistivities of RuO2 thin films. It was found that the measured room temperature resistivities increases from 2.94µΩ-m to 45.7µΩ-m when the precursor sol is aged for aged 60 days. AFM analysis on the aged films shows that the grain size and the surface roughness of the annealed films increase with the ageing of the precursor solution. From XPS analysis we have detected the presence of non-transformed RuCl3 in case of films prepared from aged solution. We propose, that solution ageing inhibits the transformation of RuCl3 to RuO2 during the annealing of the films. The deterioration of the conductivity with solution ageing is thought to be related with the chloride contamination in the annealed films.


2017 ◽  
Vol 4 (9) ◽  
pp. 1458-1464 ◽  
Author(s):  
M.-Y. Lee ◽  
D. I. Bilc ◽  
E. Symeou ◽  
Y.-C. Lin ◽  
I.-C. Liang ◽  
...  

A new p-type semiconductor Ba3Ag3InTe6 with transport properties dominated by the layer [Ag3Te4]5− distributed in the valence band.


2001 ◽  
Vol 685 ◽  
Author(s):  
Won-Jae Lee ◽  
Chang-Ho Shin ◽  
In-Kyu You ◽  
Il-Suk Yang ◽  
Sang-Ouk Ryu ◽  
...  

AbstractThe SrTa2O6 (STO) thin films were prepared by plasma enhanced atomic layer deposition (PEALD) with alternating supply of reactant sources, Sr[Ta(C2H5O)5(C4H10NO)]2 {Strontium bis-[tantalum penta-ethoxide dimethyllaminoethoxide]; Sr(Ta(OEt)5▪dmae)2} and O2plasma. It was observed that the uniform and conformal STO thin films were successfully deposited using PEALD and the film thickness per cycle was saturated at about 0.8 nm at 300°C. Electrical properties of SrTa2O6 (STO) thin films prepared on Pt/SiO2/Si substrates with annealing temperatures have been investigated. While the grain size and dielectric constant of STO films increased with increasing annealing temperature, the leakage current characteristics of STO films slightly deteriorated. The leakage current density of a 40nm-STO film was about 5×10−8A/cm2 at 3V.


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.


2019 ◽  
Vol 361 ◽  
pp. 396-402 ◽  
Author(s):  
Fangjuan Geng ◽  
Lei Yang ◽  
Bing Dai ◽  
Shuai Guo ◽  
Gang Gao ◽  
...  

2013 ◽  
Vol 2013 ◽  
pp. 1-6 ◽  
Author(s):  
Jyun-Min Lin ◽  
Ying-Chung Chen ◽  
Chi-Pi Lin

Bismuth telluride-based compounds are known to be the best thermoelectric materials within room temperature region, which exhibit potential applications in cooler or power generation. In this paper, thermal evaporation processes were adopted to fabricate the n-type Bi2Te3thin films on SiO2/Si substrates. The influence of thermal annealing on the microstructures and thermoelectric properties of Bi2Te3thin films was investigated in temperature range 100–250°C. The crystalline structures and morphologies were characterized by X-ray diffraction and field emission scanning electron microscope analyses. The Seebeck coefficients, electrical conductivity, and power factor were measured at room temperature. The experimental results showed that both the Seebeck coefficient and power factor were enhanced as the annealing temperature increased. When the annealing temperature increased to 250°C for 30 min, the Seebeck coefficient and power factor of n-type Bi2Te3-based thin films were found to be about −132.02 μV/K and 6.05 μW/cm·K2, respectively.


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