Influence of Radiation Heat Transfer on Mc-Si Ingot during Directional Solidification: A Numerical Investigation

Crystalline silicon (c‐Si) solar cells have been accepted as the only environmentally and economically acceptable alternative source to fossil fuels. The majority of commercially available solar cells of all Photovoltaic (PV) cells produced worldwide, are made of crystalline silicon. Due to their excellent price/performance ratio and their demonstrated ecological durability, crystalline silicon wafers are by far the most common absorber material used in the production of solar cells and modules today. These wafers are primarily made using either a directional solidification that produces large‐grained multi‐crystalline (mc‐Si) wafers with a greater defect density or a solar‐optimized Czochralski (Cz) growing method that produces crystalline silicon with low defect density (c‐Si). The grown crystalline wafer contains foreign atoms that enhance the wire saw damage, reduce the minority carrier lifetime as a result get the minimum conversion efficiency of the solar cells. The current review illustrates how the elements of the furnace system affect impurity production and distribution of the developed silicon ingot and how the growth process affects the chemical reaction. Additionally, it covers the outcomes of simulations and experiments conducted on the growing process of c‐Si and mc‐Si ingots and recommends the most appropriate processing parameters, geometrical system, and argon gas flow rate.

“…An argon gas purge is used to regulate the atmosphere inside the growth chamber at pressures between 20 and 100 m bar. [ 15–23 ]…”

Section: Si Ingot Growth Techniquementioning

confidence: 99%

Section: Cz Techniquementioning

confidence: 99%

A Critical Review of The Process and Challenges of Silicon Crystal Growth for Photovoltaic Applications

Sekar,

Thamotharan,

Manickam

et al. 2023

“…In order to control the heat extraction in the DS furnaces the geometrical structure of the furnace is modified. [1,2] Nagarajan et al, have investigated the addition of an insulation block in the DS furnace both numerically and experimentally. The results conclude that this modification reduces power consumption and enhances the growth rate.…”

Section: Introductionmentioning

confidence: 99%

Numerical Investigation of the Effect of Modified Heat Exchanger Block on Thermal Stress and Dislocation Density of DS‐Grown mc‐Si Ingot

Sekar,

Thamodharan,

Manikkam

et al. 2023

The present work is based on the numerical investigation of thermal stress and the dislocation density of the directional solidification (DS) grown multi‐crystalline silicon (mc‐Si) ingot. The heat exchanger block (HEB) plays the main role in the growth process, which decides the thermal stress and melt‐crystal interface of the mc‐Si ingot. The conventional furnace is modified to increase the quality of the mc‐Si ingot. The modification on the conventional furnace is done in the insulation block replaced by 1/3rd of the HEB. The HEB enhances the huge amount of heat extraction from the bottom of the crucible. The von Mises stress, dislocation density, and thermal gradient are analyzed. The thermal stress is reduced by the low thermal gradient influenced by the modified HEB. The modified HEB reduces the von Mises stress and dislocation density. The modified furnace system overcomes the conventional case ingot. The result shows that the modified furnace grown mc‐Si ingot improves the efficiency of the solar cell.

“…The quality of mc-Si ingots has been enhanced by keerthivasan et al through modifications made to the furnace geometry. [7][8][9] Extensive research has been conducted by Sugunraj et al to investigate the grain structure and impurity concentrations within mc-Si [10] and by Madhesh et al to investigate the temperature control and carbon oxygen concentration within mc-Si. [11] The saw damage removal, surface cleaning, polishing, and texturing of silicon wafer surfaces, as well as the recycling of silicon materials, are all obtained by wet-chemical etching processing.…”

Section: Introductionmentioning

confidence: 99%

“…through modifications made to the furnace geometry. [ 7–9 ] Extensive research has been conducted by Sugunraj et al. to investigate the grain structure and impurity concentrations within mc‐Si [ 10 ] and by Madhesh et al.…”

Section: Introductionmentioning

confidence: 99%

Influence of Temperature on Acid‐Based Wet Chemical Texturization for Ultralow Optical Reflectance (<2%) of mc‐Si Wafer for PV Applications

Madhesh,

Muthukumar,

Srinivasan

et al. 2023

This study proposes a method to enhance the efficiency and optical properties of silicon solar cells made from as‐cut boron‐doped p‐type multicrystalline silicon (mi‐Si) wafers through acid‐based chemical texturization. Achieving lower reflectance is crucial for improving solar cell efficiency, and this can be attained through optimized chemical etching. The research demonstrates achieving a reflectance below 2% on the wafer surface after optimal chemical etching. Wet chemical etching is employed as the surface treatment method, using the same chemical etchant with varying conditions for the texturing process. The study compares temperature‐maintained chemical etching and without temperature maintenance. The chemicals used include HF + HNO3 + CH3COOH at temperatures of 50 °C and room temperature, with etching durations of 2, 5, 10, and 15 minutes, respectively. The as‐cut boron‐doped p‐type mc‐Si wafer grains are analyzed using UV‐vis spectroscopy, optical microscopy, Fourier transform infrared spectroscopy, thickness profilometry, scanning electron microscopy, and X‐ray diffraction spectroscopy, both before and after etching. Among the different conditions tested, the chemical etchant HF + HNO3 + CH3COOH at 50 °C for a 5‐minute etching duration yields favorable results, with reflectivity below 2%. The orientation of mc‐silicon wafer grains is determined using X‐ray diffraction spectroscopy.