Advanced screen printed polymer Ag paste for HIT cells

The Photovoltaic market has grown tremendously during the past decade. HIT (Heterojuction with Intrinsic Thin layer) cells have drawn special attention because of their potential ability for further cost reduction to achieve grid parity. HIT cells have achieved higher conversion efficiency than traditional crystalline silicon solar cells, and demonstrated better performance stability at high temperature. Similar to thin film solar cell, the pastes for HIT cell are printed on TCO (transparent conductive oxide) substrate, and are required to be curable at low temperature (≤200°C) to minimize the possibility of cell degradation. In this paper we will discuss the paste requirements for HIT cell application and the effect of paste chemistry on cell performance. This paper will also present the various attributes of these pastes such as excellent electrical conductivity, strong adhesion to ITO layer, high aspect ratio and good printability.