Desenvolvimento de células solares com metalização por serigrafia : influência do emissor N+

• Ano de defesa: 2012
• Autor(a) principal: Cenci, Angélica Souza
• Orientador(a): Zanesco, Izete
• Tipo de documento: Dissertação
• Tipo de acesso: Acesso aberto
• Idioma: por
• Instituição de defesa: Pontifícia Universidade Católica do Rio Grande do Sul
• Programa de Pós-Graduação: Programa de Pós-Graduação em Engenharia e Tecnologia de Materiais
• Departamento: Faculdade de Engenharia
• País: BR
• Palavras-chave em Português: ENGENHARIA DE MATERIAIS; CÉLULAS SOLARES; ENERGIA SOLAR; SISTEMAS FOTOVOLTAICOS
• Área do conhecimento CNPq: CNPQ::ENGENHARIAS
• Link de acesso: http://tede2.pucrs.br/tede2/handle/tede/3227

The main goal of the solar cell industry is to obtain high efficiency and low production cost. One line of action is to increase the efficiency of industrial solar cell . The goal of this dissertation is to develop n+pn+ solar cells in p-type Si-Cz wafer, solar grade, with metallization by screen printing and to evaluate the influence of the n+ emitter and PV159 and PV16A silver pastes on cell efficiency. Parameters such as time, temperature of phosphorus diffusion, annealing, metal paste firing and antireflection coating thickness were optimized experimentally. We also evaluated the influence of the shadow factor metal grid, and the POCl3 concentration during P diffusion. For the metallization with the PV159 paste, it was concluded that the diffusion temperature (TD) of 875 °C and sheet resistance (R□) de 59 Ω/□ results in better efficiency of 13.7 %. With the increase in TD to 900 °C it was found that all electrical parameters tend to decrease with increasing of R□ and the better efficiency obtained was 13.4 %. It was verified that the annealing after the phosphorus diffusion hardly affects the efficiency of solar cells, however, slightly increases the junction depth. The belt speed and the temperature of the PV159 paste firing process resulting in higher efficiency and fill factor (FF) were 240 cm/min and 840 °C, respectively. It was shown that the reduction of the shadow factor from 9.4 % to 8.2 %, increased the JSC without decreasing the FF. With the PV16A paste, the TD of 875 °C results in efficiency of 13.7 %, due to the elevated FF. However, with the reduction of TD to 850 °C, the FF is reduced due to the increase of R□. With the introduction of annealing step, the JSC decreased, but the FF increased, raising the efficiency from 10.8 % to 13.2 %. The use of POCl3 concentration of 0.1 % without reducing O2 and N2 flows resulted in better efficiency for cells with PV16A paste, achieving 13.9 %. Jointly with the increase of FF, the R□ decreased, limiting the JSC. The reduction of the gas flows led to lower values of JSC, due to the increase of "dead zone" thickness. For both pastes, the FF decreased with the increase of R□.