Utilization of CaF₂/ITO Double‐Layer Anti‐Reflective Coating for Increasing the Efficiency in Rear Emitter SHJ Solar Cells

Abstract

A method to minimize optical losses in the front side of rear emitter silicon heterojunction (SHJ) solar cells by applying double-layer antireflection coating (DLARC) has been examined. The primary aim is to increase the short circuit current density (J sc ) using DLARC that is associated with the cell's absorbance. The optical and electrical properties of single-layer antireflection coating (SLARC) are studied and compared with calcium fluoride (CaF 2 )/Indium tin oxide (ITO) DLARC.OPAL 2 is utilized as a simulation tool to increase the optical properties of CaF 2 /ITO DLARC, and the experimental result verifies its validity. ITO is deposited using sputter system while thermal evaporator is utilized to deposit CaF 2 to make DLARC. The SHJ solar cell having DLARC demonstrates the average reflection of 6.55% which is 31.7% less than SLARC, that is 9.59% for the wavelength range of 300 to 1100 nm. The fabricated textured solar cell with CaF 2 /ITO DLARC shows enhancement in external quantum efficiency from 76.89% to 81.06%. It also indicates an improvement in J sc to 40.83 mA cm -2 from 39.91 mA cm -2 and having a conversion efficiency of >21% when compared with that of ITO SLARC.

Recent Applications of Antireflection Coatings in Solar Cells

“…MgF 2 is a low-refractive-index material, which is often used in combination with other materials to reduce reflection [27,28]. ITO has excellent conductivity and transmittance and is often used to prepare transparent electrodes [29]. With the continuous development of solar cells, more and more attention has been paid to the research on polymer materials and graphene (Gr) with tremendous potential in antireflection.…”

“…PMMA (polymethyl methacrylate) and PEDOT: PSS (poly (3,4-ethyleneoxythiophene): poly (sty- The structural features of silicon heterojunction solar cells (SHJs) are that a thin intrinsic amorphous silicon layer is sandwiched between c-Si and a-Si with opposite doping types [15]. SHJs have the characteristics of a simple structure, a low-temperature coefficient and process (less than 200 • C), high open-circuit voltage, and high efficiency [29]. Kunta Yoshikawa et al [84] combined interdigitated back contact and an SHJ to achieve a PCE exceeding 26%, which is closer to the theoretical limit of silicon solar cells of 29.1%.…”

“…With the ITO/SiN x /SiO x stacks, the J SC could be further increased to 42 mA/cm 2 . Muhammad Aleem Zahid et al [29] used a CaF 2 /ITO DLARC to achieve a reflectivity of 6.55% in 300-1100 nm and 4.81% in 400-700 nm. Compared with traditional ITO thin films, IZO (indium zinc oxide) thin films have excellent photoelectric properties and could also be used in SHJs.…”

Numerical Exploration and Statistical Analysis of Mathematical Parameters of Anti Reflecting Coating on Operational Parameters Improvement of Solar Cell

“…The incident light will reflect between the sloped surfaces, strengthening the interaction between the incident light and the semiconductor surface. The second layer is protected by a single or multi-layer antireflective coating [24][25][26][27][28][29][30][31][32][33][34][35][36][37][38][39][40]. These coatings are typically very thin, with an optical thickness of about one-quarter to one-half the incident wavelength.…”

“…The framework outlined illustrates a complex interplay among the material attributes, photon dynamics, and electrical properties, shaping the efficiency of solar photovoltaic (PV) cells. This underscores the significance of anti-reflective coatings in enhancing the cell's performance [18][19][20][21][22][23][24][25][26][27][28][29][30][31][32][33][34][35].…”