Numerical and experimental investigation of octagonal thermal field for improving multi-crystalline silicon ingot quality

Multi-crystalline silicon ingot casting using directional crystallisation is the most costeffective technique for the production of Si for the photovoltaic industry. Non-uniform cooling conditions and a non-planarity of the solidification front result, however, in the build-up of stresses and viscoplastic deformation. Known defects, such as dislocations and residual stresses, can then occur and reduce the quality of the produced material. Numerical simulation, combined with experimental investigation, is therefore a key tool for understanding the crystallisation process, and optimizing it. The purpose of the present work is to present an experimental furnace for directional crystallisation of silicon, and its analysis by means of numerical simulation. The complete casting procedure, i.e., including both the crystallisation phase and the subsequent ingot cooling, is simulated. The thermal field has been computed by a CFD tool, taking into account important phenomena such as radiation and convection in the melt. The transient thermal field is used as input for a thermo-elasto-viscoplastic model for the analysis of stress build-up and viscoplastic deformation during the process. Numerical analysis is employed to identify process phases where further optimisation is needed in order to reduce generated defects.

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Numerical investigation of Directional Solidification process for improving multi-crystalline silicon ingot quality for photovoltaic applications

Materials Letters ◽

10.1016/j.matlet.2018.12.129 ◽

2019 ◽

Vol 241 ◽

pp. 180-183 ◽

Cited By ~ 6

Author(s):

V. Kesavan ◽

M. Srinivasan ◽

P. Ramasamy

Keyword(s):

Directional Solidification ◽

Numerical Investigation ◽

Crystalline Silicon ◽

Solidification Process ◽

Silicon Ingot ◽

Directional Solidification Process ◽

Ingot Quality ◽

Photovoltaic Applications

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Modeling of poly-crystalline silicon ingot crystallization during casting and theoretical suggestion for ingot quality improvement

Materials Science in Semiconductor Processing ◽

10.1016/j.mssp.2016.05.013 ◽

2016 ◽

Vol 53 ◽

pp. 36-46 ◽

Cited By ~ 8

Author(s):

Amir Reza Ansari Dezfoli ◽

Weng-Sing Hwang ◽

James Augusto ◽

Anmar Khalid Shukur ◽

Shikai Tzeng

Keyword(s):

Quality Improvement ◽

Crystalline Silicon ◽

Silicon Ingot ◽

Ingot Quality

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Thermo-Mechanical Analysis of Directional Crystallisation of Multi-Crystalline Silicon Ingots

Materials Science Forum ◽

10.4028/www.scientific.net/msf.508.597 ◽

2006 ◽

Vol 508 ◽

pp. 597-602 ◽

Cited By ~ 18

Author(s):

Mohammed M'Hamdi ◽

Ernst A. Meese ◽

Harald Laux ◽

Eivind J. Øvrelid

Keyword(s):

Numerical Simulation ◽

Thermal Field ◽

Crystalline Silicon ◽

Mechanical Analysis ◽

Viscoplastic Deformation ◽

Silicon Ingot ◽

Cooling Conditions ◽

Crystallisation Process ◽

Transient Thermal

Multi-crystalline silicon ingot casting using directional crystallisation is the most costeffective technique for the production of Si for the photovoltaic industry. Non-uniform cooling conditions and a non-planarity of the solidification front result, however, in the build-up of stresses and viscoplastic deformation. Known defects, such as dislocations and residual stresses, can then occur and reduce the quality of the produced material. Numerical simulation, combined with experimental investigation, is therefore a key tool for understanding the crystallisation process, and optimizing it. The purpose of the present work is to present an experimental furnace for directional crystallisation of silicon, and its analysis by means of numerical simulation. The complete casting procedure, i.e., including both the crystallisation phase and the subsequent ingot cooling, is simulated. The thermal field has been computed by a CFD tool, taking into account important phenomena such as radiation and convection in the melt. The transient thermal field is used as input for a thermo-elasto-viscoplastic model for the analysis of stress build-up and viscoplastic deformation during the process. Numerical analysis is employed to identify process phases where further optimisation is needed in order to reduce generated defects.

Download Full-text