Made available in DSpace on 2015-04-14T13:58:57Z (GMT). No. of bitstreams: 1
445280.pdf: 9550362 bytes, checksum: 89bd2eb9be946101305ba1c7cc3020ee (MD5)
Previous issue date: 2012-12-06 / 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□. / O principal objetivo da ind?stria de c?lulas solares ? obter alta efici?ncia e baixo custo de produ??o. Uma das linhas de atua??o ? o aumento da efici?ncia de c?lulas solares industriais. O objetivo desta disserta??o ? desenvolver c?lulas solares n+pn+ em l?minas de Si-Cz do tipo p, grau solar, com metaliza??o por serigrafia e avaliar a influ?ncia do emissor n+ e das pastas de prata PV159 e PV16A. Par?metros como tempo, temperatura da difus?o de f?sforo, recozimento, processo de queima das pastas met?licas e espessura do filme antirreflexo foram otimizados experimentalmente. Tamb?m foi avaliada a influ?ncia do fator de sombra relativo ? malha met?lica, da concentra??o de POCl3 durante a difus?o de f?sforo. Para a metaliza??o com a pasta PV159, concluiu-se que a temperatura de difus?o (TD) de 875 ?C e resist?ncia de folha (R□) de 59 Ω/□ resultam na melhor efici?ncia de 13,7 %. Com o aumento da TD para 900 ?C verificou-se que todos os par?metros el?tricos tendem a diminuir com o aumento da R□, e a melhor efici?ncia obtida foi de 13,4 %. Verificou-se que o recozimento ap?s a difus?o de f?sforo praticamente n?o afeta a efici?ncia das c?lulas solares, por?m, aumenta levemente a profundidade da jun??o. A velocidade de esteira e a temperatura de queima para a pasta PV159 que resultaram em maior efici?ncia e maior fator de forma (FF) foram, 240 cm/min e 840 ?C, respectivamente. Comprovou-se que a diminui??o do fator de sombra de 9,4 % para 8,2 %, aumentou a JSC sem reduzir o FF. Com a pasta PV16A, a TD de 875 ?C resultou na efici?ncia de 13,7 %, devido ao elevado FF. No entanto, com a redu??o da TD para 850 ?C, o FF sofre redu??o, devido ao aumento da R□. Com a introdu??o da etapa de recozimento, a JSC diminuiu, por?m o FF aumentou, elevando a efici?ncia de 10,8 % para 13,2 %. A concentra??o de POCl3 de 0,1 % sem redu??o da vaz?o de O2 e N2 resultou na melhor efici?ncia para c?lulas com a pasta PV16A, de 13,9 %. Juntamente com o aumento do FF, a R□ diminuiu, limitando a JSC. A redu??o do fluxo dos gases levou a valores menores de JSC, devido ao aumento da espessura da zona morta. Para ambas as pastas, o FF reduziu-se com o aumento da R□.
| Identifer | oai:union.ndltd.org:IBICT/oai:tede2.pucrs.br:tede/3227 |
| Date | 06 December 2012 |
| Creators | Cenci, Ang?lica Souza |
| Contributors | Zanesco, Izete |
| Publisher | Pontif?cia Universidade Cat?lica do Rio Grande do Sul, Programa de P?s-Gradua??o em Engenharia e Tecnologia de Materiais, PUCRS, BR, Faculdade de Engenharia |
| Source Sets | IBICT Brazilian ETDs |
| Language | Portuguese |
| Detected Language | English |
| Type | info:eu-repo/semantics/publishedVersion, info:eu-repo/semantics/masterThesis |
| Format | application/pdf |
| Source | reponame:Biblioteca Digital de Teses e Dissertações da PUC_RS, instname:Pontifícia Universidade Católica do Rio Grande do Sul, instacron:PUC_RS |
| Rights | info:eu-repo/semantics/openAccess |
| Relation | -7432719344215120122, 500, 600, -655770572761439785 |
Page generated in 0.0019 seconds