Fabrication of devices using vacuum deposited a–Si

1989 ◽  
Vol 67 (4) ◽  
pp. 195-198 ◽  
Author(s):  
R. D. Audas ◽  
D. E. Brodie
Keyword(s):  
Temperature Conductivity ◽  
Room Temperature Conductivity ◽  
Reactive Evaporation ◽  
Boron Doped ◽  
Optical Bandgaps ◽  
Temperature Activation ◽  
P Type ◽  
Phosphorus Doped ◽  
Term Objective

The long-term objective of this work is to produce a stable, efficient amorphous Si (a-Si) solar cell by a safe and inexpensive method. A process of reactive evaporation in a silane ambient was developed. This technique permits the fabrication of "intrinsic-like" a-Si:H. p-Type and n-type samples (carrier type was confirmed by Seebeck measurements) were prepared by the coevaporation of boron or reactive evaporation in a phosphorus ambient. The intrinsic-like samples have a room temperature conductivity of about 2 × 10−12 S cm−1, high temperature activation energies of 0.9 eV, and optical bandgaps near 1.8 eV. An all-amorphous Si:H pin diode was fabricated using this reactive evaporation process. The device consists of a tantalum contact, 20 – 40 nm of phosphorus doped a-Si:H, 300 – 400 nm of undoped a-Si:H, 20 – 40 nm of boron doped a-Si:H, and another tantalum contact.

a-Si:N:H prepared by reactive evaporation in ammonia vapour

1987 ◽  
Vol 65 (8) ◽  
pp. 1020-1022
Author(s):  
R. D. Audas ◽  
D. E. Brodie
Keyword(s):  
Thin Films ◽  
Room Temperature ◽  
Activation Energies ◽  
High Activation ◽  
Temperature Conductivity ◽  
Room Temperature Conductivity ◽  
Reactive Evaporation ◽  
Ammonia Vapour ◽  
Optical Bandgaps ◽  
P Type

The reactive evaporation of Si in an ammonia ambient has been used to produce a-Si:N:H thin films. These films are "intrinsic-like" with low room-temperature conductivities (<10−12 S∙cm−1), high activation energies (0.9 eV), and high optical bandgaps (1.9 eV). Films prepared in this manner have been doped using co-evaporation of antimony (n type) and indium (p type). The addition of 2 at.% indium or antimony results in an increase in the room-temperature conductivity by eight and six orders of magnitude respectively. The undoped and doped samples are photoconductive when illuminated with a quartz-halogen source.

Synthesis, Electrical and Humidity Sensing Properties of BaTiO3 Nanofibers via Electrospinning

2011 ◽  
Vol 418-420 ◽  
pp. 684-687 ◽  
Author(s):  
Hong Di Zhang ◽  
Yun Ze Long ◽  
Zhao Jian Li ◽  
Bin Sun ◽  
Chen Hao Sheng
Keyword(s):  
Room Temperature ◽  
Humidity Sensor ◽  
Annealing Process ◽  
Temperature Conductivity ◽  
Room Temperature Conductivity ◽  
Humidity Sensing ◽  
P Type ◽  
Application Prospects ◽  
Humidity Sensing Properties ◽  
Scanning Electron

Barium titanate (BTO, BaTiO3) nanofiber was prepared via electrospinning and followed annealing process. The as-spun and calcined BTO nanofibers were characterized by a scanning electron microscope (SEM). After annealing at 800 °C in air for 3 h, polycrystalline BTO nanofibers with 120-200 nm in diameter were successfully obtained. I-V characteristic curves of single BTO nanofiber were measured. The p-type semiconducting fiber shows a room-temperature conductivity of about 0.3 S/cm. In addition, the small humidity hysteresis demonstrates the application prospects of electrospun BTO nanofibers in the fabrication of a high-sensitive humidity sensor.

Phosphorus and Boron Doping of a-Si:H Effects of Deposition Temperature

1987 ◽  
Vol 95 ◽  
Author(s):  
M. J. M. Pruppers ◽  
K. H. M. Maessen ◽  
J. Bezemer ◽  
F. H. P. M. Habraken ◽  
W. F. van der Weg
Keyword(s):  
Deposition Temperature ◽  
Room Temperature ◽  
Hydrogenated Amorphous Silicon ◽  
Boron Doping ◽  
Dark Conductivity ◽  
Temperature Conductivity ◽  
Room Temperature Conductivity ◽  
Boron Doped ◽  
Hydrogenated Amorphous ◽  
Deposited Films

AbstractHeavily phosphorus and boron doped hydrogenated amorphous silicon films were deposited in the temperature range 50 to 300 °C. Concentrations of P, B and H, IR spectra and room temperature conductivity have been measured. When the deposition temperature is raised from 50 to 300 °C the concentration of P increases, while the concentration of B decreases. The dark conductivity of both P and B doped films decreases dramatically when the deposition temperature is lowered. We interpret these results on the basis of assumptions concerning the microstructure of the deposited films, and especially the variation of this structure with deposition temperature.

Microcrystal Si Films Prepared by Remote Plasma CVD

1989 ◽  
Vol 164 ◽  
Author(s):  
Sung Chul Kim ◽  
Jung Tae Hwang ◽  
Seung Kyu Lee ◽  
Chang Young Jung ◽  
Sung Moo Soe ◽  
...  
Keyword(s):  
Rf Power ◽  
Plasma Cvd ◽  
Remote Plasma ◽  
Temperature Conductivity ◽  
Room Temperature Conductivity ◽  
Hydrogen Dilution ◽  
Power Yield ◽  
Si Films ◽  
Hydrogen Radicals ◽  
P Type

AbstractThe effects of deposition temperature, rf power and hydrogen dilution ratio on the growth, structure and transport of p-type microcrystal(μc-) Si films deposited by remote plasma CVD have been investigated. While low substrate temperature and low rf power yield small grain sizes, high temperature and high rf power tend to supress the growth of grains. The etching of Si by hydrogen radicals plays an important role to grow μc-Si, but excess etching supresses the growth of crystallites. We obtained 400 A of grain size and 3.5 S/cm of room temperature conductivity for p-type μ-Si.

Some Recent Advances on the n-Type Doping of Diamond

2005 ◽  
Vol 108-109 ◽  
pp. 703-708
Author(s):  
Jacques Chevallier ◽  
T. Kociniewski ◽  
Cecile Saguy ◽  
R. Kalish ◽  
C. Cytermann ◽  
...  
Keyword(s):  
Electrical Activity ◽  
Ionization Energy ◽  
Boron Doped Diamond ◽  
Shallow Donors ◽  
Compensation Ratio ◽  
Boron Doped ◽  
Recent Advances ◽  
High Ionization ◽  
P Type ◽  
Phosphorus Doped

The n-type doping of diamond with phosphorus suffers from defects reducing the electron mobilities and inducing some degree of compensation. In addition, the relatively high ionization energy (0.6 eV) of phosphorus severely limits the electrical activity of the dopants. Here, we present two recent advances of the n-type doping of diamond. One is based on the significant reduction of the compensation ratio of highly compensated phosphorus-doped diamond by thermal annealings. The second one presents the possibility of converting p-type boron-doped diamond into n-type by deuterium diffusion and formation of deuterium-related shallow donors with ionization energy of 0.33 eV.

Revealing Mysteries of Hall Experiments on a-Si:H and a-SiC:H

1993 ◽  
Vol 297 ◽  
Author(s):  
C. E. Nebel ◽  
R.A Street
Keyword(s):  
Amorphous Silicon ◽  
Hall Coefficient ◽  
Temperature Regime ◽  
Carrier Density ◽  
Accurate Determination ◽  
Drift Mobility ◽  
Boron Doped ◽  
P Type ◽  
Phosphorus Doped

Hall experiments performed on intrinsic, phosphorus and boron doped a-Si:H and a-SiC:H in the temperature regime 200 K ≤ T ≤400 K are introduced and discussed. The data confirm the double sign anomaly meaning the Hall coefficient is p-type on intrinsic and phosphorus doped a-Si:H and a-SiC:H, and n-type on boron doped a-Si:H. The Hall mobilities, μH, are significantly smaller than the drift mobilities, decreasing with increasing doping and/or carbon content. μH of holes is about half that for electron which indicate that μH scales approximately with 1/Eg where Eg is the tail slope. The presented interpretation of the Hall coefficient, that is introduced to be a function of Hall- and drift-mobility, enables the accurate determination of the carrier density in intrinsic and doped amorphous silicon and alloys from Hall data.

scholarly journals Room-temperature synthesized copper iodide thin film as degenerate p-type transparent conductor with a boosted figure of merit

2016 ◽  
Vol 113 (46) ◽  
pp. 12929-12933 ◽  
Author(s):  
Chang Yang ◽  
Max Kneiβ ◽  
Michael Lorenz ◽  
Marius Grundmann
Keyword(s):  
Thin Films ◽  
Figure Of Merit ◽  
Room Temperature ◽  
Visible Spectral Range ◽  
Transparent Conductors ◽  
Transparent Conductor ◽  
Temperature Dependent ◽  
Temperature Conductivity ◽  
Room Temperature Conductivity ◽  
P Type

A degenerate p-type conduction of cuprous iodide (CuI) thin films is achieved at the iodine-rich growth condition, allowing for the record high room-temperature conductivity of ∼156 S/cm for as-deposited CuI and ∼283 S/cm for I-doped CuI. At the same time, the films appear clear and exhibit a high transmission of 60–85% in the visible spectral range. The realization of such simultaneously high conductivity and transparency boosts the figure of merit of a p-type TC: its value jumps from ∼200 to ∼17,000 MΩ−1. Polycrystalline CuI thin films were deposited at room temperature by reactive sputtering. Their electrical and optical properties are examined relative to other p-type transparent conductors. The transport properties of CuI thin films were investigated by temperature-dependent conductivity measurements, which reveal a semiconductor–metal transition depending on the iodine/argon ratio in the sputtering gas.

Turkish Muslims in a German city: Entrepreneurial and residential self-determination

2015 ◽  
Vol 12 (1) ◽  
pp. 1-12
Author(s):  
Sarah Hackett
Keyword(s):  
Residential Patterns ◽  
Academic Literature ◽  
Self Employment ◽  
German City ◽  
Post War ◽  
Oral History Interviews ◽  
The City ◽  
Insight Into ◽  
Term Objective

Drawing upon a collection of oral history interviews, this paper offers an insight into entrepreneurial and residential patterns and behaviour amongst Turkish Muslims in the German city of Bremen. The academic literature has traditionally argued that Turkish migrants in Germany have been pushed into self-employment, low-quality housing and segregated neighbourhoods as a result of discrimination, and poor employment and housing opportunities. Yet the interviews reveal the extent to which Bremen’s Turkish Muslims’ performances and experiences have overwhelmingly been the consequences of personal choices and ambitions. For many of the city’s Turkish Muslim entrepreneurs, self-employment had been a long-term objective, and they have succeeded in establishing and running their businesses in the manner they choose with regards to location and clientele, for example. Similarly, interviewees stressed the way in which they were able to shape their housing experiences by opting which districts of the city to live in and by purchasing property. On the whole, they perceive their entrepreneurial and residential practices as both consequences and mediums of success, integration and a loyalty to the city of Bremen. The findings are contextualised within the wider debate regarding the long-term legacy of Germany’s post-war guest-worker system and its position as a “country of immigration”.

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