Solar

Bulk

Silicon

SiOnyx’s laser texture provides an efficiency boost and lowers your dollar per watt cost by reducing surface reflectance and achieving tighter process controls. Further cost savings can be realized by migrating to thinner wafers with almost no loss in current due to superior light trapping.

Black Silicon

How It Works

SiOnyx’s proprietary process can be seamlessly dropped into existing cell manufacturing lines on top of isotexture or alkaline texture to further lower reflectance with a demonstrated absolute efficiency boost of 0.3-0.5%. For multicrystalline cells, the saw damage removal and texture steps can be decoupled by performing a deep acid polish etch and using SiOnyx single-sided laser texture. This is ideal for solar cell architectures that require a planar backside for passivation and local contacts.

SiOnyx’s laser texture process is fully compatible with both n- and p-type silicon, and is completely independent of crystal grain orientation. Furthermore, since it provides enhanced quantum efficiency in the red and near infrared portions of the solar spectrum, the process is complementary to existing selective emitter solutions that provide a current boost in the blue wavelengths.

Above: Standard 156mm multicrystalline silicon cells with screen printed contacts and aluminum back surface field. Cells were processed and tested at ISC Konstanz (Germany). SiOnyx laser texture provides a clear boost in current with no voltage degradation, resulting in enhanced efficiency. Additionally the process results in tighter efficiency binning.

	Isotexture	Alkaline Texture	SiOnyx Laser Texture
Decouple saw damage removal & texture processes to maximize V_oc & J_sc	Not separable
Low reflectance	22+% refl. pre-ARC
Fast / inline		Too slow for inline
Robust features, <1 μm height	Deep saw damage holes	Pyramids 3-10 μm
Consume <2 μm of silicon to form texture	Consumes 4+ μm	Consumes 10+ μm
Independent of grain orientation		Only suitable for (001) surfaces