Nmos Transistors Fabricated by Simultaneous Laser-Assisted Crystallization and Diffusion on Silicon on Electro-Optic PLZT

1988 ◽  
Vol 100 ◽  
Author(s):  
J. H. Wang ◽  
T. H. Lin ◽  
S. C. Esener ◽  
S. Dasgupta ◽  
S. H. Lee

ABSTRACTSimultaneous CW laser assisted crystallization and diffusion for fabricating NMOS transistors on Si/SiO2/PLZT is presented. Hall effect measurement (mobility 74cm2V−1sec×1019cm−3 of phosphorus dopping), crystal delineation (grain size 50×30μm) and Raman spectroscopy (stress 6.0×109dynescm−2) indicated that good quality doped silicon crystal film can be produced with this method. NMOS transistors fabricated by this technology show good performances such as high breakdown voltage (45 V), small leakage current (2 nA/μm), reasonable channel carrier mobility (140cm2V−1−1) and photosensitivity (1.5 A/W).

1981 ◽  
Vol 4 ◽  
Author(s):  
T. J. Stultz ◽  
J. F. Gibbons

ABSTRACTStructural and electrical characterization of laser recrystallized LPCVD silicon films on amorphous substrates using a shaped cw laser beam have been performed. In comparing the results to data obtained using a circular beam, it was found that a significant increase in grain size can be achieved and that the surface morphology of the shaped beam recrystallized material was much smoother. It was also found that whereas circular beam recrystallized material has a random grain structure, shaped beam material is highly oriented with a <100> texture. Finally the electrical characteristics of the recrystallized film were very good when measured in directions parallel to the grain boundaries.


Author(s):  
Ryo Oishi ◽  
Koji ASAKA ◽  
Bolotov Leonid ◽  
Noriyuki Uchida ◽  
Masashi Kurosawa ◽  
...  

Abstract A simple method to form ultra-thin (< 20 nm) semiconductor layers with a higher mobility on a 3D-structured insulating surface is required for next-generation nanoelectronics. We have investigated the solid-phase crystallization of amorphous Ge layers with thicknesses of 10−80 nm on insulators of SiO2 and Si3N4. We found that decreasing the Ge thickness reduces the grain size and increases the grain boundary barrier height, causing the carrier mobility degradation. We examined two methods, known effective to enhance the grain size in the thicker Ge (>100 nm). As a result, a relatively high Hall hole mobility (59 cm2/Vs) has been achieved with a 20-nm-thick polycrystalline Ge layer on Si3N4, which is the highest value among the previously reported works.


1997 ◽  
Vol 481 ◽  
Author(s):  
E. Pineda ◽  
T. Pradell ◽  
D. Crespo ◽  
N. Clavaguera ◽  
J. ZHU ◽  
...  

ABSTRACTThe microstructure developed in primary crystallizations is studied under realistic conditions. The primary crystallization of an amorphous alloy is modeled by considering the thermodynamics of a metastable phase transition and the kinetics of nucleation and crystal growth under isothermal annealing. A realistic growth rate, including an interface controlled growth at the beginning of the growth of each single grain and diffusion controlled growth process with soft impingement afterwards is considered. The reduction in the nucleation rate due to the compositional change in the remaining amorphous matrix is also taken into account. The microstructures developed during the transformation are obtained by using the Populational KJMA method, from the above thermodynamic and kinetic factors. Experimental data of transformed fraction, grain density, average grain size, grain size distribution and other related parameters obtained from annealed metallic glasses are modeled.


2020 ◽  
Vol 12 (27) ◽  
pp. 30565-30571
Author(s):  
Epimitheas Georgitzikis ◽  
Jan Genoe ◽  
Paul Heremans ◽  
David Cheyns

2020 ◽  
Vol 234 (4) ◽  
pp. 699-717
Author(s):  
James Hirst ◽  
Sönke Müller ◽  
Daniel Peeters ◽  
Alexander Sadlo ◽  
Lukas Mai ◽  
...  

AbstractThe temporal evolution of photogenerated carriers in CuWO4, CuO and WO3 thin films deposited via a direct chemical vapor deposition approach was studied using time-resolved microwave conductivity and terahertz spectroscopy to obtain the photocarrier lifetime, mobility and diffusion length. The carrier transport properties of the films prepared by varying the copper-to-tungsten stoichiometry were compared and the results related to the performance of the compositions built into respective photoelectrochemical cells. Superior carrier mobility was observed for CuWO4 under frontside illumination.


Author(s):  
S. Basu ◽  
B. J. Lee ◽  
Z. M. Zhang

This paper describes an experimental investigation on the infrared radiative properties of heavily-doped silicon (Si) at room temperature. Lightly-doped Si wafers were ion implanted with boron and phosphorus atoms to doping concentrations of 1×1020 and 1×1021 cm−3. Rapid thermal annealing was performed to activate the implanted dopants. A Fourier-transform infrared spectrometer was employed to measure the normal transmittance as well as reflectance of the samples in the spectral region from 2 to 20 μm. Accurate carrier mobility and ionization models were identified after carefully reviewing the available literature, and then incorporated into Drude model to predict the dielectric function of doped Si. The radiative properties of doped Si samples were calculated by treating the doped region as multilayer thin films of different doping concentrations on a thick Si substrate. The measured spectral transmittance and reflectance agree well with the model predictions. The results obtained from this study will facilitate the future applications of heavily-doped Si in semiconductor as well as MEMS devices.


2006 ◽  
Vol 976 ◽  
Author(s):  
Christopher Carlton ◽  
P. J. Ferreira

AbstractAn inverse Hall-Petch effect has been observed for nanocrystalline materials by a large number of researchers. This result implies that nanocrystalline materials get softer as grain size is reduced below a critical value. Postulated explanations for this behavior include dislocation based mechanisms and diffusion based mechanisms. In this paper, we report an explanation for the inverse Hall-Petch effect based on the statistical absorption of dislocations by grain boundaries, showing that the yield strength is both dependent on strain rate and temperature, and that it deviates from the Hall-Petch relationship at a critical grain size.


2019 ◽  
Vol 33 (06) ◽  
pp. 1950033
Author(s):  
E. Mansouri ◽  
J. Karamdel ◽  
M. T. Ahmadi ◽  
M. Berahman

Investigation on (2-dimensional) (2D) materials is growing significantly due to the fundamental electronic properties in the direct inherent bandgap, higher carrier mobility, and easier exfoliation. Phosphorene as a new 2D configuration has presented excellent potential in electronic and optoelectronic applications. In this study, the conductivity of monolayer phosphorene and Einstein’s relations as fundamental parameters in semiconductor manufacturing are analytically modeled. In addition, dependency of conductivity on normalized Fermi energy ([Formula: see text]) is demonstrated. According to the simulation results, conductivity and Einstein’s relation are completely dependent on temperature, therefore, rising up the temperature leads to conductivity and diffusion coefficient (Dn) growth. Indeed, conductivity is saturated when the normalized Fermi energy exceeds than 6. Also, the conductivity and Einstein’s relation dependency to voltage are studied. Results show that carrier conductivity and the electron diffusion coefficient (Dn) increase by amplifying the voltage.


2010 ◽  
Vol 1270 ◽  
Author(s):  
Mujeeb Ullah ◽  
Andrey K. Kadashchuk ◽  
Philipp Stadler ◽  
Alexander Kharchenko ◽  
Almantas Pivrikas ◽  
...  

AbstractThe critical factor that limits the efficiencies of organic electronic devices is the low charge carrier mobility which is attributed to disorder in organic films. In this work we study the effects of active film morphology on the charge transport in Organic Field Effect Transistors (OFETs). We fabricated the OFETs using different substrate temperature to grow different morphologies of C60 films by Hot Wall Epitaxy. Atomic Force Microscopy images and XRD results showed increasing grain size with increasing substrate temperature. An increase in field effect mobility was observed for different OFETs with increasing grain size in C60 films. The temperature dependence of charge carrier mobility in these devices followed the empirical relation named as Meyer-Neldel Rule and showed different activation energies for films with different degree of disorder. A shift in characteristic Meyer-Neldel energy was observed with changing C60 morphology which can be considered as an energetic disorder parameter.


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