The Supply Side Of Metallization Pastes

• Pastes system required for solar cell metallization varies according to cell architecture and advanced metallization concept
• TaiyangNews Market Survey on Metallization Pastes categorizes pastes classified into 7 different categories based on their application
• The survey lists total of 111 pastes models from 9 pastes suppliers

Screen printing has been the workhorse for solar cell metallization and is expected to remain so at least for the foreseeable future. Apart from screen printing, the PV industry has also been working on several other application methods such as dispensing, rotations printing and plating. Most alternate metallization techniques still rely on pastes as process consumable, except for plating. This means that the role of metallization pastes in the advancement of PV remains pronounced, though the composition would be changed according to the technology employed to apply it.

However, pastes today are mainly designed for screen printing process. Metallization pastes are a uniformly dispersed mixture of several organic and inorganic materials. Different milling and mixing processes are employed in the making of these pastes.

Not only do standard solar cells require 3 different kinds of metallization pastes, which holds true for PERC cells as well, all high-efficiency cell architectures and advanced metallization concepts also require a specialized paste system.

TaiyangNews has published the 3^rd edition of its Market Survey on Metallization Pastes discussing different aspects of these pastes that are classified into 7 different categories based on their application in today's mass production. These are:

• Front-contact silver pastes (p-type)
• Pastes used in double and dual printing
• Aluminum paste used for the formation Back Surface Field (Al-BSF)
• Rear tabbing silver pastes
• Complete paste systems for Passivated Emitter and Rear Cell (PERC) architecture
• Pastes for n-type cells
• Low temperature curable pastes, typically used for heterojunction cells and some thin-film PV technologies

Technically speaking, passivated contacts is also a new and emerging technology that requires a special paste system. However, this technology is generally adapted to PERT, thus pastes for passivated contacts are featured in the sections of this core technology stream.

Different pastes makers are offering various pastes compositions suitable for the above-mentioned applications. A total of 9 pastes suppliers have responded to our enquiry and provided data for 111 pastes models. The above table (main picture) provides an overview of applications supported these 9 pastes makers by offering supportive products. Pastes for PERC front contacts are the applications that are in the main focus of the majority of the paste makers.

For details on further important aspects of Metallization Pastes, see our TaiyangNewsMarket Survey Metallization Pastes 2019/20, which can be downloaded for free.