Development of a selective electroforming process for micro-sized probe tips used in LCD inspection machines

Abstract

A probe station is an inspection apparatus that automatically transfers liquid crystal display (LCD) panels and separates defective LCD products using a micro-probe unit. However, as the number of pixels increases in LCD screens, the size of the inspecting probe unit has to decrease. There are many limits to the conventional methodology when it comes to fabricating micro-sized probes. In this study, a selective electroforming process was developed and a micro-probe tip was fabricated using this process. Selective electroforming is a high-precision fabricating process where a non-conductive barrier layer is deposited on a conductive wafer and the conductive parts are electroformed using only Ni. Finally, using the selective electroforming process, the micro-sized probe was fabricated with a shape error of less than 0.1%.