This study explores the conditions necessary for low temperature fabrication of Al2O3 thin films by the ALD technique. Properties of the Al2O3 thin films were anlysised by variable-angle spectroscopic ellipsometer (VASE) and X-ray photoemission spectroscopy(XPS). | Journal of Science & Technology 126 (2018) 059-062 Growth and Characterization of Al2O3 Ultra-Thin Film as a Passivation Layer for Silicon Solar Cells Mateus Manuel Neto1,3, Luu Thi Lan Anh1*, Nguyen Trung Do1, Nguyen Hoang Thoan1, Nguyen Ngoc Trung1, Chung Han Wu2, Vo Thach Son1 1 Hanoi University of Science and Technology, No. 1, Dai Co Viet, Hai Ba Trung, Hanoi, Viet Nam 2 Boviet Solar Technology 3 Agostinho Neto University, Avenida 4 de Fevereiro 7 Luanda, Angola Received: January 17, 2018; Accepted: June 25, 2018 Abstract The properties of aluminum oxide (Al2O3) films have shown excellent performances such as remarkable passivation behaviors on both n- and p-type Si sufaces. For fabrication of Al2O3 one can use a cost-saving deposition technique called atomic layer deposition (ALD). This study explores the conditions necessary for low temperature fabrication of Al2O3 thin films by the ALD technique. Properties of the Al2O3 thin films were anlysised by variable-angle spectroscopic ellipsometer (VASE) and X-ray photoemission spectroscopy(XPS). Thicknesses of the films were investigated depending on deposition cycles. The estimated deposition growth rate was Å/cycle at deposition temperature of about 200oC. The Al2O3 ultrathin films can be used as a passivation layer for Si thin film solar cells. Keywords: atomic layer deposition ALD, Al2O3 ultra-thin film, interface passivation, Si solar cells 1. Introduction* is more than what is required. Each ALD deposition consists of the following steps: (i) deposition of the first reactant, (ii) purge of the nonreacted reactants and volatile products from the first step with inert gas, (iii) deposition of the second reactant and (iv) purge of the non-reacted reactants and volatile products from the third step. An excellent interface passivation has been considered as a key point for high efficiency solar cells as passivated emitter and rear cell. To suppress the surface/interface recombination, two .
