Uniform and Directed Crystallization of Deposited a­Si on Glass Substrates at Linear Velocities Of 1 to 20 Meters Per Second

1981 ◽  
Vol 4 ◽  
Author(s):  
D. Bensahel ◽  
G. Auvert ◽  
V. T. Nguyen ◽  
G. A. Rozgonyi
Keyword(s):  
Phase Boundary ◽  
Laser Power ◽  
Crystallization Process ◽  
Solid Phase ◽  
Crystallization Front ◽  
Continuous Furnace ◽  
Directed Crystallization ◽  
Glass Substrates ◽  
Explosive Crystallization ◽  
Scan Speed

ABSTRACTIt has been found that careful control of the laser power and scan speed will convert deposited a­Si into continuous lines of uniformly crystallized silicon. Two solid phase “explosive” crystallization front velocities of 1000 cm/sec and 1400 cm/sec have been experimentally determined by matching the laser scan velocity with the runaway a–c phase boundary. If solid phase explosive crystallization is suppressed by pre-annealing, then a liquid assisted runaway crystallization velocity of 220 cm/sec is observed, as well as a continuous furnace-like crystallization process at 250 cm/sec.

Low-Temperature PECVD Polysilicon Crystallization by Rapid Thermal Processing

1998 ◽  
Vol 508 ◽  
Author(s):  
Mark Stewart ◽  
Howard Hovagimian ◽  
Jecko Arakkal ◽  
Sambit Saha ◽  
Miltiadis K. Hatalis
Keyword(s):  
Thermal Processing ◽  
Solid Phase ◽  
Rapid Thermal Processing ◽  
Statistical Design ◽  
Laser Crystallization ◽  
Polysilicon Film ◽  
Pressure Surface ◽  
Glass Substrates ◽  
Annealing Conditions ◽  
Scan Speed

AbstractThis work investigates the solid phase crystallization of PECVD amorphous silicon films by rapid thermal processing (RTP) as an alternative to laser crystallization. It is shown that PECVD films can be crystallized by RTP at temperatures compatible with glass substrates. A statistical design approach was used to investigate the effect of the various deposition and annealing conditions on the crystallization temperature, material properties and TFT device performance. The investigated variables include deposition temperature, rf power, pressure, surface treatments, dehydrogenation treatment, source gas, dilutant gas, and RTP scan speed. Important deposition and crystallization parameters will be discussed regarding polysilicon film optimization.

Fast Scanned Energy Beam Induced Explosive Crystallization of Ion Implantation Amorphized Poly and Single Crystal Silicon Substrates

1981 ◽  
Vol 4 ◽  
Author(s):  
M. Lerme ◽  
T. Ternisien D'ouville ◽  
Duy-Phach Vu ◽  
A. Perio ◽  
G.A. Rozgonyi ◽  
...  
Keyword(s):  
Single Crystal ◽  
Solid Phase ◽  
Single Crystal Silicon ◽  
Grain Structure ◽  
Silicon Substrates ◽  
Crystal Silicon ◽  
Energy Beam ◽  
Glass Substrates ◽  
Explosive Crystallization ◽  
Si Films

ABSTRACTExplosive crystallisation induced by an electron beam and by a CW Ar+ laser operating in fast scanning mode is observed for the first time on amorphized silicon layers created by implantation on either polycrystalline films deposited on Si02 or single crystal silicon substrates. The grain structure in the explosive crescents is studied by preferential chemical etching in conjunction with Nomarski optical microscopy, SEM and TEM. The results are similar to the so-called solid-phase explosive crystallization previously observed in a-Si films deposited on glass substrates.

scholarly journals Расчет динамики границы аморфная фаза-кристалл при твердофазной взрывной кристаллизации

2021 ◽  
Vol 63 (11) ◽  
pp. 1927
Author(s):  
А.А. Чеврычкина ◽  
Н.М. Бессонов ◽  
А.Л. Корженевский
Keyword(s):  
Differential Equation ◽  
Constant Velocity ◽  
Solid Phase ◽  
Crystallization Front ◽  
The Self ◽  
Mode Transition ◽  
Explosive Crystallization ◽  
Theoretical Results ◽  
Front Motion ◽  
Oscillating Mode

The nonlinear differential equation described a dynamics of solid-phase explosive crystallization front in a much larger parameters domain in comparison with the theoretical results available in literature was obtained. The features of the self-oscillating mode transition of the front motion to the mode of its self-propagation with a constant velocity was numerically studied in detail.

Initiation of the Explosive Crystallization Process in Amorphous Alloys of the Fe-Zr System by Pulse Laser Treatment

2019 ◽  
Vol 11 (2) ◽  
pp. 02004-1-02004-5
Author(s):  
T. L. Tsaregradskaya ◽  
◽  
Yu. A. Kunitskyi ◽  
О. О. Kаlenyk ◽  
I. V. Plyushchay ◽  
...  
Keyword(s):  
Laser Treatment ◽  
Pulse Laser ◽  
Amorphous Alloys ◽  
Crystallization Process ◽  
Explosive Crystallization

Solid Phase Growth of some Metal and Metal Oxide Thin Films on Sapphire and Quartz Glass Substrates

2013 ◽  
Vol 753 ◽  
pp. 505-509
Author(s):  
Yuichi Sato ◽  
Toshifumi Suzuki ◽  
Hiroyuki Mogami ◽  
Fumito Otake ◽  
Hirotoshi Hatori ◽  
...  
Keyword(s):  
Thin Films ◽  
Quartz Glass ◽  
Glass Substrate ◽  
Solid Phase ◽  
Quartz Glass Substrate ◽  
Heteroepitaxial Growth ◽  
Phase Growth ◽  
Single Crystalline ◽  
Glass Substrates ◽  
Amorphous Quartz

Solid phase growth of thin films of copper (Cu), aluminum (Al) and zinc oxide (ZnO) on single crystalline sapphire and quartz glass substrates were tried by heat-treatments and their crystallization conditions were investigated. ZnO thin films relatively easily recrystallized even when they were deposited on the amorphous quartz glass substrate. On the other hand, Cu and Al thin films hardly recrystallized when they were deposited on the quartz glass substrate. The metal thin films could be recrystallized at only extremely narrow windows of the heat-treatment conditions when they were deposited on the single crystalline sapphire substrate. The window of the solid phase heteroepitaxial growth condition of the Al film was wider than that of the Cu film.

Solute Segregation and Dynamics of Solid-Phase Crystallization In in and Sb-Implanted Silicon

1981 ◽  
Vol 4 ◽  
Author(s):  
J. Narayan ◽  
G. L. Olson ◽  
O. W. Holland
Keyword(s):  
Laser Power ◽  
Solid Phase ◽  
Solute Segregation ◽  
Dislocation Loops ◽  
Solid Phase Crystallization ◽  
Time Resolved ◽  
Plan View ◽  
Ion Channeling ◽  
Retrograde Solubility ◽  
Transmission Electron

ABSTRACTTime-resolved-reflectivity measurements have been combined with transmission electron microscopy (cross-section and plan-view), Rutherford backscattering and ion channeling techniques to study the details of laser induced solid phase epitaxial growth in In+ and Sb+ implanted silicon in the temperature range from 725 to 1500 °K. The details of microstructures including the formation of polycrystals, precipitates, and dislocations have been correlated with the dynamics of crystallization. There were limits to the dopant concentrations which could be incorporated into substitutional lattice sites; these concentrations exceeded retrograde solubility limits by factors up to 70 in the case of the Si-In system. The coarsening of dislocation loops and the formation of a/2<110>, 90° dislocations in the underlying dislocation-loop bands are described as a function of laser power.

Measurement of the Melt Pool Length During Single Scan Tracks in a Commercial Laser Powder Bed Fusion Process

2017 ◽  
Author(s):  
J. C. Heigel ◽  
B. M. Lane
Keyword(s):  
Laser Power ◽  
High Speed ◽  
Infrared Camera ◽  
Powder Bed Fusion ◽  
Single Track ◽  
Laser Powder Bed Fusion ◽  
Powder Bed ◽  
Melt Pool ◽  
Significant Difference ◽  
Scan Speed

This work presents high speed thermographic measurements of the melt pool length during single track laser scans on nickel alloy 625 substrates. Scans are made using a commercial laser powder bed fusion machine while measurements of the radiation from the surface are made using a high speed (1800 frames per second) infrared camera. The melt pool length measurement is based on the detection of the liquidus-solidus transition that is evident in the temperature profile. Seven different combinations of programmed laser power (49 W to 195 W) and scan speed (200 mm/s to 800 mm/s) are investigated and numerous replications using a variety of scan lengths (4 mm to 12 mm) are performed. Results show that the melt pool length reaches steady state within 2 mm of the start of each scan. Melt pool length increases with laser power, but its relationship with scan speed is less obvious because there is no significant difference between cases performed at the highest laser power of 195 W. Although keyholing appears to affect the anticipated trends in melt pool length, further research is required.

Optical, Structural and Electrical Characteristics of Explosively Crystallized Si Thin Films on Glass Substrates

1981 ◽  
Vol 4 ◽  
Author(s):  
G. Auvert ◽  
D. Bensahel ◽  
A. Perio ◽  
F. Morin ◽  
G.A. Rozgonyi ◽  
...  
Keyword(s):  
Thin Films ◽  
Electrical Properties ◽  
Laser Annealing ◽  
The State ◽  
Electrical Characteristics ◽  
Glass Substrates ◽  
Explosive Crystallization ◽  
Cw Laser ◽  
Structural And Electrical Properties ◽  
Si Films

ABSTRACTExplosive Crystallization occurs in cw laser annealing on a-Si films deposited on glass substrates at laser scan speeds higher than 30 cm/sec. Optical, structural and electrical properties of the crystallized films at various laser scan speeds confirm the existence of two kinds of explosive growth depending on the state of crystallinity of the starting material.

Uniform Poly-Si TFTs for AMOLEDs Using Field-Enhanced Rapid Thermal Annealing

2007 ◽  
Vol 124-126 ◽  
pp. 447-450 ◽  
Author(s):  
Hyoung June Kim
Keyword(s):  
Thermal Annealing ◽  
Rapid Thermal Annealing ◽  
Thin Film Transistors ◽  
Solid Phase ◽  
Radiative Heating ◽  
Solid Phase Crystallization ◽  
Glass Substrates ◽  
Grain Structures ◽  
Amorphous Si ◽  
Si Thin Film

Polycrystalline Si thin film transistors (TFTs) have been fabricated through solid phase crystallization using field-enhanced rapid thermal annealing (FE-RTA) system. The system consists of inline furnace modules for preheating and cooling of the glass substrates and a process module for rapid radiative heating combined with alternating magnetic field induction. The FE-RTA system enables crystallization of amorphous Si at high throughputs without any glass damages. While the typical grain structures of poly-Si by FE-RTA are similar to those of solid phase crystallization, the residual amorphous Si and intragranular defects are reduced.

scholarly journals Manufacturing Aluminum/Multiwalled Carbon Nanotube Composites via Laser Powder Bed Fusion

Materials ◽  
2020 ◽  
Vol 13 (18) ◽  
pp. 3927
Author(s):  
Eo Ryeong Lee ◽  
Se Eun Shin ◽  
Naoki Takata ◽  
Makoto Kobashi ◽  
Masaki Kato
Keyword(s):  
Elastic Modulus ◽  
Carbon Nanotube ◽  
Energy Density ◽  
Laser Power ◽  
Multiwalled Carbon Nanotube ◽  
Powder Bed Fusion ◽  
Laser Powder Bed Fusion ◽  
Multiwalled Carbon ◽  
Powder Bed ◽  
Scan Speed

This study provides a novel approach to fabricating Al/C composites using laser powder bed fusion (LPBF) for a wide range of structural applications utilizing Al-matrix composites in additive manufacturing. We investigated the effects of LPBF on the fabrication of aluminum/multiwalled carbon nanotube (Al/MWCNT) composites under 25 different conditions, using varying laser power levels and scan speeds. The microstructures and mechanical properties of the specimens, such as elastic modulus and nanohardness, were analyzed, and trends were identified. We observed favorable sintering behavior under laser conditions with low energy density, which verified the suitability of Al/MWCNT composites for a fabrication process using LPBF. The size and number of pores increased in specimens produced under high energy density conditions, suggesting that they are more influenced by laser power than scan speed. Similarly, the elastic modulus of a specimen was also more affected by laser power than scan speed. In contrast, scan speed had a greater influence on the final nanohardness. Depending on the laser power used, we observed a difference in the crystallographic orientation of the specimens by a laser power during LPBF. When energy density is high, texture development of all samples tended to be more pronounced.

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