scholarly journals Optimal Magnetic Graphite Heater Design for Impurity Control in Single-Crystal Si Grower Using Crystal Growth Simulation

Processes ◽  
2021 ◽  
Vol 10 (1) ◽  
pp. 70
Author(s):  
Hye Jun Jeon ◽  
Hyeonwook Park ◽  
Salh Alhammadi ◽  
Jae Hak Jung ◽  
Woo Kyoung Kim
Keyword(s):  
Crystal Growth ◽  
Single Crystal ◽  
Molten State ◽  
Growth Simulation ◽  
Impurity Control ◽  
Average Oxygen Concentration ◽  
Heater Design ◽  
Oxygen Impurities ◽  
Crystal Interface ◽  
Coil Shape

In this paper, we report a successfully modified single-crystal Si growth furnace for impurity control. Four types of arbitrary magnetic heater (AMGH) systems with 3, 4, 5, and poly parts were designed in a coil shape and analyzed using crystal growth simulation. The concentration of oxygen impurities in single-crystal Si ingots was compared among the designed AMGHs and a normal graphite heater (NGH). The designed AMGHs were confirmed to be able to control turbulence and convection in a molten state, which created a vortex that influenced the oxygen direction near the melt–crystal interface. It was confirmed that replacing NGH with AMGHs resulted in a reduction in the average oxygen concentration at the Si melt–crystal interface by approximately 4.8%.

scholarly journals Numerical Simulation of the Effect of Heater Position on the Oxygen Concentration in the CZ Silicon Crystal Growth Process

2012 ◽  
Vol 2012 ◽  
pp. 1-6 ◽  
Author(s):  
Ying-Yang Teng ◽  
Jyh-Chen Chen ◽  
Chung-Wei Lu ◽  
Cheng-Chuan Huang ◽  
Wan-Ting Wun ◽  
...  
Keyword(s):  
Crystal Growth ◽  
Oxygen Concentration ◽  
Concentration Distribution ◽  
Growth Process ◽  
Silicon Crystal ◽  
Crucible Wall ◽  
Crystal Growth Process ◽  
Silicon Melt ◽  
Average Oxygen Concentration ◽  
Crystal Interface

We perform numerical simulations to analyze the effect of the position of the heater on the thermal and flow fields and the oxygen concentration distribution during the industrial Cz silicon crystal growth process. The amount of oxygen released from the silica crucible to the silicon melt during the growth process can be lowered by adjusting the heater position to decrease the temperature on the crucible wall. During growth of the crystal body, there is a significant decrease in the gradient of the oxygen concentration along the melt-crystal interface due to the stronger Taylor-Proudman vortex, which is generated by the crucible and crystal rotation. There is a significant reduction in the average oxygen concentration at the melt-crystal interface for longer crystal lengths because of the lower wall temperature, smaller contact surface between the crucible wall and the melt and the stronger Taylor-Proudman vortex.

Seeded Crystal Growth of Yba2Cu3O6.5 in Semisolid Melts

1997 ◽  
Vol 12 (4) ◽  
pp. 880-890 ◽  
Author(s):  
S. Honjo ◽  
M. J. Cima ◽  
M. C. Flemings ◽  
T. Ohkuma ◽  
H. Shen ◽  
...  
Keyword(s):  
Crystal Growth ◽  
Single Crystal ◽  
Single Crystals ◽  
Particle Concentration ◽  
Volume Fraction ◽  
Isothermal Solidification ◽  
The Other ◽  
Oxide Content ◽  
Particle Segregation ◽  
Crystal Interface

Melt textured single crystals of YBa2Cu3O6.5 (123) superconductors were produced by isothermal solidification from a semisolid melt using single crystal NdBa2Cu3O6.5 or SmBa2Cu3O6.5 seeds. The microstructure within the single crystals shows an inhomogeneous segregation of Y2BaCO5 (211) particles trapped in the 123 crystals during solidification. The concentration of 211 particles varies with the crystal axes in 123 crystals produced from precursors with compositions of 80 wt.% 123 powder and 20 wt.% excess 211. The 211 particle concentration along the c-axis in the crystal is much lower than that along the a- or b-axes during initial crystallization. This concentration increases in both directions as the crystal grows larger. The 211 concentration along the c-axis increases more quickly than the concentration along the other axes during solidification, which allows the 211 concentration to approach that on the other axes as the solidification continues. 211 particle segregation in stoichiometric 123 samples formed “X”-shaped tracks instead of the variations in 211 concentration described above. A single crystal growth model of 123 is proposed and employed to interpret these experimental observations. Quenched samples were prepared to investigate the volume fraction of 211 particles in the liquid phase. A constant distribution of 211 particles was observed in the liquid, except very near the crystal interface, where the 211 concentration decreased rapidly. Copper oxide content in the liquid was also measured. It is found that the copper content is lower at the (001) interface compared with (100) or (010) interfaces.

Single Crystal Growth of High-Pressure Phases of Ice and Salt Hydrate Far Below the Original Melting Point by Mixing Alcohol: Crystal Structure Determination of Magnesium Chloride Heptahydrate

2020 ◽  
Author(s):  
Keishiro Yamashita ◽  
Kazuki Komatsu ◽  
Hiroyuki Kagi
Keyword(s):  
Crystal Structure ◽  
High Pressure ◽  
Crystal Growth ◽  
Single Crystal ◽  
Room Temperature ◽  
Growth Technique ◽  
Salt Hydrate ◽  
X Ray

An crystal-growth technique for single crystal x-ray structure analysis of high-pressure forms of hydrogen-bonded crystals is proposed. We used alcohol mixture (methanol: ethanol = 4:1 in volumetric ratio), which is a widely used pressure transmitting medium, inhibiting the nucleation and growth of unwanted crystals. In this paper, two kinds of single crystals which have not been obtained using a conventional experimental technique were obtained using this technique: ice VI at 1.99 GPa and MgCl<sub>2</sub>·7H<sub>2</sub>O at 2.50 GPa at room temperature. Here we first report the crystal structure of MgCl2·7H2O. This technique simultaneously meets the requirement of hydrostaticity for high-pressure experiments and has feasibility for further in-situ measurements.

Unsteady 3D and analytical analysis of segregation process in floating zone silicon single crystal growth

2009 ◽  
Vol 45 (4) ◽  
pp. 549-556 ◽  
Author(s):  
K. Lācis ◽  
◽  
A. Muižnieks ◽  
N. Jēkabsons ◽  
A. Rudevičs ◽  
...  
Keyword(s):  
Crystal Growth ◽  
Single Crystal ◽  
Single Crystal Growth ◽  
Silicon Single Crystal ◽  
Floating Zone ◽  
Analytical Analysis ◽  
Segregation Process

scholarly journals Control of Oxygen Impurities in a Continuous-Feeding Czochralski-Silicon Crystal Growth by the Double-Crucible Method

Crystals ◽  
2021 ◽  
Vol 11 (3) ◽  
pp. 264
Author(s):  
Wenhan Zhao ◽  
Jiancheng Li ◽  
Lijun Liu
Keyword(s):  
Oxygen Concentration ◽  
Silicon Crystal ◽  
Cost Effective ◽  
Czochralski Method ◽  
Crucible Wall ◽  
Oxygen Impurity ◽  
Continuous Feeding ◽  
The Impact ◽  
Oxygen Impurities ◽  
Crystal Interface

The continuous-feeding Czochralski method is a cost-effective method to grow single silicon crystals. An inner crucible is used to prevent the un-melted silicon feedstock from transferring to the melt-crystal interface in this method. A series of global simulations were carried out to investigate the impact of the inner crucible on the oxygen impurity distributions at the melt-crystal interface. The results indicate that, the inner crucible plays a more important role in affecting the O concentration at the melt-crystal interface than the outer crucible. It can prevent the oxygen impurities from being transported from the outer crucible wall effectively. Meanwhile, it also introduces as a new source of oxygen impurity in the melt, likely resulting in a high oxygen concentration zone under the melt-crystal interface. We proposed to enlarge the inner crucible diameter so that the oxygen concentration at the melt-crystal interface can be controlled at low levels.

Sign in / Sign up

Export Citation Format

Share Document