Vapour-Phase and Solid-Phase Epitaxy of Silicon on Solid-Phase Crystallised Seed Layers for Solar Cells Application

Abstract EN

Vapour-phase and solid-phase epitaxy are used for thickening of a solid-phasecrystallised silicon seed layer on glass.

Cross-sectional transmission microscopeimages confirm that a transfer of crystallographic information has taken placefrom the seed layer into the epilayers.

X-ray diffraction, scanning electron microscopy,and transmission electron microscopy reveal that the density of planardefects (mainly on { 111 } plains) in the vapour-phase epitaxial sample is muchhigher than in the solid-phase epitaxial sample.

These planar defects can act asrecombination centres for free-charge carriers.

Consequently, PC1D modelled minoritycarrier diffusion length in the vapour-phase grown epilayer is 50% shorterthan that in the solid-phase grown epilayer.

As a result, a solar cell grown bysolid-phase epitaxy achieves open circuit voltage of 468 mV, short circuit currentof 9.17 mA/cm2, and photovoltaic conversion efficiency at 2.75% which are allhigher than those of the solar cell grown by vapour-phase epitaxy on the sameseed layer, 400 mV, 7.28 mA/cm2, 1.69%, respectively.

It proves that solid-phase epitaxy is more suitable for the solar cell growth on the solid-phase crystallisedsilicon seed layer than vapour-phase epitaxy.