Surface polarity control to reinforce dopant adhesion in laser doping of textured silicon

Abstract

Increasing energy conversion efficiency without any extra cost is required for crystalline silicon (c-Si) solar cells. Laser doping (LD) can meet these requirements because it can be performed in an ambient atmosphere at room temperature. In this study, spin-coated phosphorus silicate glass (PSG) was formed on textured c-Si as a precursor for LD. We found that after LD, the reinforcement of the interface between PSG and the Si surface improved the photovoltaic characteristics V oc and J sc. The interface was reinforced by changing the c-Si surface from hydrophobic to hydrophilic before spin coating. The reinforced interface led to a reduction in the number of surface voids and an enhancement of the transfer of dopant atoms.

Boron laser doping using spin-on dopant for textured crystalline silicon solar cell

“…Moreover, the dopant profile became inhomogeneous owing to the large number of voids. 28) In the present study, a strongly adhered interface enabled the textured surface to absorb the laser power homogeneously. The shallow region of the textured surface was melted by the laser power and recrystallized with the incorporation of boron atoms.…”

“…In a previous study, the effect of the interface between the precursor and the substrate on emitter characteristics was large in LD using silica-based SoD. 28) When using a silica-based doping precursor, an incident laser of wavelength 355 nm penetrates the precursor and is absorbed by the Si substrate. The laser power absorbed in substrates is converted into heat that melts the substrate.…”

Non-destructive Raman evaluation of a heavily doped surface layer fabricated by laser doping with B-doped Si nanoparticles

“…The carrier concentration of the heavily B-doped surface layer is larger than approximately 10 19 cm À 3 . A laser doping method has been developed for heavily doped surface layers [2][3][4][5][6][7][8]. This technique has some advantages associated with the use of laser light.…”