Advanced Materials for Electronics

Solar Cell Etchants

Antireflective surface treatment

Solar Cell Etchants are anisotropic type etchants for surface treatment of silicon solar cells and are used to improve cell efficiency.

SOLAR CELL ETCHANT – Type 200
Alkali – based, low toxicity

SOLAR CELL ETCHANT – Type 300
Ethylenediamine – based, safer to use

FEATURES:

  • Textured surface
  • Reduced light reflection
  • Improved cell efficiency

SOLAR CELL ETCHANTS
DESCRIPTION

Solar cell etchants are anisotropic type etchants for the surface treatment of silicon solar cells and are used to improve cell efficiency.
The surface treatment leads to the formation of tetrahedral structures which reduce reflection losses of incident solar energy. The textured surface structure actually promotes interaction of light and favors light absorption. Reduced efficiency due to light reflection is, therefore, minimized.

Two etching systems are offered: SCE-200 is alkali-based and has a low toxicity. SCE-300 is ethylenediamine-based and has a moderate etch rate.

PROPERTIES OF SOLAR CELL ETCHANTS

SCE-200 SCE-300
Appearance Odorless, colorless liquid Clear yellow liquid
Composition Alkali-based Ethylenediamine-based
Etch Tank Glass Glass
Oper. Temp 75-100 °C 118 °C
Preferred Orientation < 100 > < 100 >
Appearance Black Black
Etch Rate ———————- 25 m /hr.
Etch Surface
Pyramid size
Reflection Loss
Etch time
1-3
50 %
1 hour
10
> 50 %
5-10 minutes

APPLICATION:

The etching process using Type 300 is best carried out in flask fitted with a reflux condenser. An open system may be used for Type 200. The flask should be heated gently so that the etchant is just at the boiling point.