Merck’s ‘isishape’ etching concepts boost crystalline solar cells efficiencies

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  All of Merck’s concepts are said to lead to efficiency increases from 0.2 to 0.5% absolute as a minimum.

Merck has developed an alternative structuring technology with its etching pastes and is offering patterning concepts under the ‘isishape’ product portfolio. isishape ‘SolarEtch’ was used in the first industrial selective emitter production and became a proven structuring method in various production lines of leading solar cell manufacturers. These material concepts are able to be used to optimized new cell designs that seek to provide higher cell efficiencies at a competitive cost structure.

Problem

The PV market is highly competitive and requires new smart ways to create advantages and unique selling points from successful companies in this field. Improved efficiency and additional process optimizations with smallest investments are essential for the solar cell manufacturers. New cell designs for improved performance are already under development and lead to new process solutions.

Solution

Merck's isishape SolarEtch product program offers a broad range of structuring materials that enable simplified and environmentally friendly processes and improved efficiency for the manufacturing of today's and tomorrow's solar cells for e.g. selective emitter (SE), metal wrap through (MWT), local back surface field (LBSF) or other modern cell designs. The structuring of SiO2, SiNx and/or Si run precise and selective by isishape. All of Merck’s concepts are said to lead to efficiency increases from 0.2 to 0.5% absolute as a minimum. The isishape process consists of 3 steps. First, is the application by screen printing or by another printing technique, the activation of the etching process through temperature settings and thirdly, a rinsing step to remove the etched materials and paste residues.

Applications

Selective emitter (SE), metal wrap through (MWT), local back surface field (LBSF) or other modern cell designs as well as edge isolation.

Platform

isishape products are well-balanced paste formulations, which safeguard the workers and equipment. Also, cleaning in DI water does not require any organic detergents. Both features result in extremely low COD (Chemical Oxygen Demand) and BOD (Biological Oxygen Demand) values, allowing for a green factory concept. Under the recommended process conditions, exhausts can be released into the air without further treatment

Availability

Currently under regular mass production.