Poly Silicon and BSG Etching

Poly Silicon and BSG Etch for TOPCon Manufacturing

The Alkaline Poly–Si and BSG Etching Inline System achieves a perfect cleaning of the sunny side for n- and p-doped poly silicon and Borosilicate glass removal.

Product benefits

Significantly lower chemistry costs

Ready for M12 with thickness down to 100μm

Single side poly-Si etch along with doped glass etching

Patented water mask

Stable process without cooling unit

Shortest maintenance times due to good accessibility and easy cleaning

Details

The Alkaline Poly-Si and BSG Etching Inline System combines several process steps in a modular system. On the one hand the front side poly silicon warp around on the wafer generated during the Poly-Si process is unilaterally isolated from the front side of the wafer followed by a borosilicate or phosphorous glass removal.

With the Poly-Si and BSG Etching Inline System, SCHMID has a perfect solution for cleaning the front side of a TOPCon cell prior to passivation and antireflection coating in its portfolio with lowest chemical consumption.

Due to the inline concept an outstanding wafer to wafer uniformity is achieved along with the capability to process wafer thicknesses down to 100μm. In addition, processing at about 80 °C ensures a high etching rate and thus a small footprint of the system. During both the Poly-Si removal and doped glass removal the rear Poly-Si and tunnel oxide is protected by the water mask developed and patented by SCHMID.

Special transport rollers ensure that the chemistry comes into contact exclusively with the frontside, thus reducing the chemistry consumption. In addition, all processes are running in one system reducing the required number of systems, automation and avoids the usage of cassettes.

Technical Data

Throughput (M12):

5,000 wafers/h (5 tracks)
10,000 wafers/h (10 tracks)
Further throughputs configurable

Wafer size:

M2 – M12

Breakage rate:

< 0,05 %

Process media:

HF
KOH
Additives

Other equipments for photovoltaics & glass

AGTex

Surface finishing for glass
The AGTex offers innovative methods for processing and finishing glass surfaces. The technology is particularly suitable for the production of antireflection and antiglare coatings on glass.

Learn more

Alkaline Texturing

Efficient texturing of mono-crystalline wafers
The Alkaline Texturing Inline System of SCHMID ensures the most efficient texturing of mono-crystalline wafers.

Learn more

APCVD System

Low cost inline deposition of thin films
The 5500 series APCVD system is well suited for low cost high-volume processing for all cell architectures requiring single or multi-layer dielectric thin film deposition.

Learn more

Edge Isolation & PSG Etching

Single-sided edge isolation for maximum efficiency
The Edge Isolation + PSG Etching Inline System fully automatically achieves a perfect edge isolation. In combination with the patented water mask the emitter is optimally isolated.

Learn more