Photovoltaic cell etching pictures

Can plasma etching be used to make solar cells?

The one in image (C) is a maple leaf-shaped cell of 0.081 mm demonstrating the capability of plasma etching to fabricate versatile shapes of solar cells. In these images, it can be seen that the mesa size is close to the cell size, which limits material losses.

What is etching process in solar cell processing?

Etching is a process which removes material from a solid (e.g., semiconductor or metal). The etching process can be physical and/or chemical, wet or dry, and isotropic or anisotropic. All these etch process variations can be used during solar cell processing.

How do you Etch A solar cell wafer?

An example of “saw damage” is shown in Figure 1 for a wafer which was sawn using diamond wire sawing. Therefore, it is necessary to etch 10 µm (slurry based sawing) or 5 µm (diamond wire sawing) of each side of the wafer before further solar cell processing and a wet alkaline etch process is commonly used for this purpose.

What is physical etching?

Physical etching or sputtering is a dry process where the material is removed due to ion bombardment. The ion bombardment is delivered by a plasma. This process is known to : be chemically unselective – depends only on the surface binding energy and the masses of the targets and projectiles,

Why is Etch A chemically unselective process?

be chemically unselective – depends only on the surface binding energy and the masses of the targets and projectiles, be very sensitive to the angle of incidence of the ion and therefore anisotropic in nature, and the only etch process able to remove involatile products from the surface.

How is plasma etching done?

Plasma etching is stopped in the middle cell base (InGaAs), solution H 2 SO 4:H 2 O 2:H 2 O (1:10:20) allows to etch until the back surface field (BSF) (InGaP) which can then be etch with H 3 PO 4:HCl (1:4) to expose the second tunnel junction. As for the top cell, the sidewalls are protected during the wet etching.