Electronic transport study of high deposition rate HWCVD a-Si:H by the microwavephotomixing technique

2001 ◽  
Vol 664 ◽  
Author(s):  
S.R. Sheng ◽  
R. Braunstein ◽  
B.P. Nelson ◽  
Y. Xu
Keyword(s):  
Substrate Temperature ◽  
Deposition Rate ◽  
Flow Rate ◽  
Electronic Transport ◽  
High Deposition Rate ◽  
Deposition Pressure ◽  
Film Properties ◽  
High Quality ◽  
Deposition Rates ◽  
Potential Fluctuations

ABSTRACTThe electronic transport properties of high deposition rate a-Si:H films prepared by HWCVD have been investigated in detail by employing the microwave photomixing technique. The high deposition rates (up to 1 µm/min.) were achieved by adding a second filament, increasing deposition pressure, silane flow rate, and decreasing filament-to-substrate distance. The effect of the deposition rate on the resultant film properties with respect to the substrate temperature, deposition pressure and silane flow rate was studied. It was found that the film transport properties do not change monotonically with increasing deposition rate. The photoconductivity peaks at ∼70-90 Å/s, where both the drift mobility and lifetime peak, consistent with the deposition rate dependence of the range and depth of the potential fluctuations. High quality, such as a photoconductivity-to-dark-conductivity ratio of ∼105 and nearly constant low charged defect density, can be maintained at deposition rates up to ∼150 Å/s, beyond which the film properties deteriorate rapidly as a result of an enhanced effect of the long-range potential fluctuations due to a considerable increase in the concentration of the charged defects. Our present results indicate that medium silane flow rate, low pressure, and higher substrate temperature are generally required to maintain high quality films at high deposition rates.

Deposition of High Quality SiO2 Films Using Teos by ECR Plasma

1995 ◽  
Vol 396 ◽  
Author(s):  
K. Sano ◽  
H. Tamamaki ◽  
M. Nomura ◽  
S. Wickramanayaka ◽  
Y. Nakanishi ◽  
...  
Keyword(s):  
Substrate Temperature ◽  
Deposition Rate ◽  
Cyclotron Resonance ◽  
Electron Cyclotron Resonance ◽  
Film Properties ◽  
High Quality ◽  
Deposition Rates ◽  
Sio2 Films ◽  
Silicon Source ◽  
Ecr Plasma

AbstractSiO2 thin firms were fabricated in a remote electron cyclotron resonance (ECR) plasma by tctraethoxysilane (TEOS) as the silicon source. Oxygen was used as the plasma gas. A mesh was placed between the TEOS gas outlet and the substrate. In the present investigation a-SiO2 films were deposited with and without the mesh and film properties were studied comparatively. The deposition rate increased when the mesh was attached. The optimum deposition rate is observed when the mesh voltage was zero, that is the mesh was grounded. The deposition rates of both methods were also dependnt on the TEOS flow rate, applied microwave power and the substrate temperature. These three parameters have significant roles in controlling the film quality. Good quality SiO2 films can be obtained with a higher deposition rate when a mesh is attached.

Hetero-Epitaxial Growth of 3C-SiC on Silicon Substrates by Plasma Assisted CVD

2006 ◽  
Vol 527-529 ◽  
pp. 299-302
Author(s):  
Hideki Shimizu ◽  
Yosuke Aoyama
Keyword(s):  
Substrate Temperature ◽  
Single Crystal ◽  
Epitaxial Growth ◽  
Deposition Rate ◽  
Crystalline Structure ◽  
Flow Rate ◽  
Silicon Substrates ◽  
High Quality ◽  
Sic Films ◽  
Lower Substrate Temperature

3C-SiC films grown on carbonized Si (100) by plasma-assisted CVD have been investigated with systematic changes in flow rate of monosilane (SiH4) and propane (C3H8) as source gases. The deposition rate of the films increased monotonously and the microstructures of the films changed from 3C-SiC single crystal to 3C-SiC polycrystal with increasing flow rate of SiH4. Increasing C3H8 keeps single crystalline structure but results in contamination of α-W2C, which is a serious problem for the epitaxial growth. To obtain high quality 3C-SiC films, the effects of C3H8 on the microstructures of the films have been investigated by reducing the concentration of C3H8. Good quality 3C-SiC single crystal on Si (100) is grown at low net flow rate of C3H8 and SiH4, while 3C-SiC single crystal on Si (111) is grown at low net flow rate of C3H8 and high net flow rate of SiH4. It is expected that 3C-SiC epitaxial growth on Si (111) will take placed at a higher deposition rate and lower substrate temperature than that on Si (100).

Low Temperature Deposited High Quality ITO Films Prepared by E-Beam Evaporation

1990 ◽  
Vol 187 ◽  
Author(s):  
C. S. Chang ◽  
J. C. Wang ◽  
L. C. Kuo
Keyword(s):  
Electron Beam ◽  
Low Temperature ◽  
Substrate Temperature ◽  
Optimal Condition ◽  
Deposition Rate ◽  
Oxygen Pressure ◽  
Electron Beam Evaporation ◽  
Film Properties ◽  
High Quality ◽  
Ito Films

AbstractAn electron beam evaporation method has been used to prepare tin doped indium oxide (ITO) films with 95 wt.% In2O3 and 5 wt.% SnO2 in an oxygen atmosphere. It was found that the deposition rate and oxygen pressure strongly influence the film properties when the substrate temperature was lower than 200°C. In an optimal condition, highly transparent (transmittance ˜ 90% at wavelength 570 nm) and conductive (resistivity – 3×10−4Ω-cm) films of thickness around 2000 Å at substrate temperature as low as 180°C can be obtained.

Relation between Growth Precursors and Film Properties for Plasma Deposition of a-Si:H at Rates up to 100 Å/s

2000 ◽  
Vol 609 ◽  
Author(s):  
W.M.M. Kessels ◽  
A.H.M. Smets ◽  
J.P.M. Hoefnagels ◽  
M.G.H. Boogaarts ◽  
D.C. Schram ◽  
...  
Keyword(s):  
Substrate Temperature ◽  
Deposition Rate ◽  
Surface Reaction ◽  
Film Growth ◽  
Plasma Deposition ◽  
Reaction Probability ◽  
Film Properties ◽  
Deposition Rates ◽  
Minor Contribution ◽  
A Minor

ABSTRACTFrom investigations on the SiH3 and SiH radical density and the surface reaction probability in a remote Ar-H2-SiH4 plasma, it is unambiguously demonstrated that the a-Si:H film quality improves significantly with increasing contribution of SiH3 and decreasing contribution of very reactive (poly)silane radicals. Device quality a-Si:H is obtained at deposition rates up to 100 Å/s for conditions where film growth is governed by SiH3 (contribution ∼90%) and where SiH has only a minor contribution (∼2%). Furthermore, for SiH3 dominated film growth the effect of the deposition rate on the a-Si:H film properties with respect to the substrate temperature is discussed.

Impact of Deposition Rate on the Structural and Magnetic Properties of Sputtered Ni/Cu Multilayer Thin Films

2017 ◽  
Vol 73 (1) ◽  
pp. 85-90 ◽  
Author(s):  
Ali Karpuz ◽  
Salih Colmekci ◽  
Hakan Kockar ◽  
Hilal Kuru ◽  
Mehmet Uckun
Keyword(s):  
Thin Films ◽  
Magnetic Properties ◽  
Deposition Rate ◽  
High Rate ◽  
Cubic Phase ◽  
High Deposition Rate ◽  
Multilayer Thin Films ◽  
Face Centered Cubic ◽  
Deposition Rates ◽  
Cu Films

AbstractThe structural and corresponding magnetic properties of Ni/Cu films sputtered at low and high deposition rates were investigated as there is a limited number of related studies in this field. 5[Ni(10 nm)/Cu(30 nm)] multilayer thin films were deposited using two DC sputtering sources at low (0.02 nm/s) and high (0.10 nm/s) deposition rates of Ni layers. A face centered cubic phase was detected for both films. The surface of the film sputtered at the low deposition rate has a lot of micro-grains distributed uniformly and with sizes from 0.1 to 0.4 μm. Also, it has a vertical acicular morphology. At high deposition rate, the number of micro-grains considerably decreased, and some of their sizes increased up to 1 μm. The surface of the Ni/Cu multilayer deposited at the low rate has a relatively more grainy and rugged structure, whereas the surface of the film deposited at the high rate has a relatively larger lateral size of surface grains with a relatively fine morphology. Saturation magnetisation, Ms, values were 90 and 138 emu/cm3 for deposition rates of 0.02 and 0.10 nm/s, respectively. Remanence, Mr, values were also found to be 48 and 71 emu/cm3 for the low and high deposition rates, respectively. The coercivity, Hc, values were 46 and 65 Oe for the low and high Ni deposition rates, respectively. The changes in the film surfaces provoked the changes in the Hc values. The Ms, Mr, and Hc values of the 5[Ni(10 nm)/Cu(30 nm)] films can be adjusted considering the surface morphologies and film contents caused by the different Ni deposition rates.

Very Wide-Gap and Device-Quality a-Si:H from Highly H2 Diluted SiH4 Plasma Decomposed by High RF Power

1999 ◽  
Vol 557 ◽  
Author(s):  
N. Terada ◽  
S. Yata ◽  
A. Terakawa ◽  
S. Okamoto ◽  
K. Wakisaka ◽  
...  
Keyword(s):  
Flow Rate ◽  
Gas Flow ◽  
High Deposition Rate ◽  
Rf Power ◽  
Gas Flow Rate ◽  
Dilution Ratio ◽  
Dilution Technique ◽  
Film Properties ◽  
Wide Gap ◽  
Hydrogenated Amorphous

AbstractThe H2 dilution technique at a high deposition rate (RD) was investigated by depositing hydrogenated amorphous silicon (a-Si:H) under a high if power density of 750 mW/cm2, which is 20 times as large as that of conventional conditions. It was found that the H2 dilution ratio γ ( = [H2 gas flow rate] / [SiH4 gas flow rate]) tendency of the film properties, such as the H content (CH), optical gap (Eopt), SiH2/SiH and photoconductivity (σph) of a-Si:H is different for the high rf power (750 mW/cm2) and the medium rf power (75 mW/cm2) conditions. Under medium rf power, the CH, Eopt and SiH2/SiH decrease as γ increases. Under the high if power, on the contrary, the CH and Eopt, monotonously increase while maintaining a low SiH2/SiH and a high σph of 10-6 S/cm as γ increases. These results suggest that increasing the rf power enhances the H incorporation reactions due to H2 dilution. It is thought that a high rf power causes the depletion of SiH4 and hence the extinction of H radicals, expressed by SiH4 + H* → SiH3* + H2, is suppressed. A high H radical density enhances the incorporation of H into a-Si:H, resulting in very wide-gap a-Si:H with a high CH, Consequently, very wide-gap a-Si:H with device-quality (Eopt of 1.82 eV with an (αhv)1/3 plot, corresponding to > 2.1 eV with Tauc's plot, and σph of 10-6 S/cm) can be obtained at a high RD of 12 Å/s without carbon alloying.

High-quality and low-temperature epitaxial Si films deposited at very high deposition rate

2001 ◽  
Vol 225 (2-4) ◽  
pp. 335-339 ◽  
Author(s):  
Ralf B. Bergmann ◽  
Lars Oberbeck ◽  
Thomas A. Wagner
Keyword(s):  
Low Temperature ◽  
Deposition Rate ◽  
High Deposition Rate ◽  
High Quality ◽  
Si Films ◽  
Very High
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