Optimization of laser doping process in crystalline silicon solar cells

Yıl 2013, Cilt: 3 Sayı: 3, 711 - 716, 01.09.2013

ABHISHEK Sharan Basudev Prasad

Öz

A large area selective emitter patterning scheme is developed and reported in the present study that features a single additional step compared to the standard process. Initially, trials are conducted to achieve a uniform base sheet resistance of 100±10 Ω/sq in p-type c-Si wafers using POCl3 diffusion on a large area 156 x 156 mm silicon wafers. Thereafter, employing a nanosecond, Q-switched, green laser and phosphosilicate glass layer (PSG) as a dopant source, areas below the front contact fingers are heavily doped while areas between them are kept lowly doped, thus realizing a selective emitter. This study refers to optimization of diffusion parameters to achieve uniform diffusion of base sheet resistance of 100±10 Ω/sq and optimization of laser parameters for achieving localized regions of high doping to attain selective emitter structure.

Anahtar Kelimeler

Laser, Doping, Diffusion, Crystalline silicon solar cell, sheet resistance.

Kaynakça

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