Dry Film Photoresist Application to a Printed Circuit Board (Pcb) using a Maskless Photolithography Method

Abstract

This paper offers an alternative method of making PCB routing using a negative dry film photoresist and a maskless photolithography method. The objective of this research is to determine the correct parameters for the process of making PCB design easier, cheaper and safer. Electronic circuit design was created on a laptop or PC using Autodesk EAGLE software with a combination of result is black and blue light color. PCB routing design was inserted into a PowerPoint slide to display on a commercial Digital Light Processing (DLP) projector. No modifications were made to a projector, which was mounted directly on a stand with a downward facing position. The projector lamp replaced an ultraviolet or X-ray source during the exposure process, exposing PCB coated in negative dry film photoresist. After the exposure process, the PCB was inserted into the developer solution, causing the blue light irradiated part to remain while the blackened sections dissolved. The PCB was then added to an etching solution to scrape the copper unprotected by the photoresist. The PCB was finally soaked in a remover solution to remove the photoresist. Once complete, the process generated a laptop-designed PCB routing. Electrical lines can be created using this method with a size of 100 µm and a lane edge deviation of 5 µm. The goal of research to make PCB routing cheaper, easier and safer was achieved. Evidenced by the installation of electronic components and then tested, the results are all components function well.

Introduction of Photopolymerization Technology and Application

“…As the key of photolithography, photoresist refers to thin film materials whose solubility and adhesion change significantly after exposure by light sources, then the micro-patterns can be obtained through development, etching and other processes. [97] It is widely employed in the fields of printed circuit boards (PCB), [98][99][100] display device, [101][102][103] integrated circuit, [104] and other fine graphics processing. Photoresist can be divided into positive photoresist and negative photoresist on the basis of the area retained after development, in which negative photoresist is photocurable materials.…”