Laser Assisted Bonding (LAB) Based Flip-Chip Process for Fine Pitch Solder Bumps Device Using Laser Non-Conductive Paste (NCP)

Non-Conductive Paste (NCP) or Non-Conductive Film (NCF) materials are thermosetting materials commonly employed to establish electrical interconnection between the bumps on the upper component and the substrate through a thermo-compression (TC) bonding process. However, the TC-NCF (Thermo-Compression Non-Conductive Film) process has very low yields due to the difficulty in maintaining uniform temperature and the requirement of high pressure for the semiconductor device. Additionally, TC-NCF has drawbacks, including warpage leading to misalignment when bonding thin devices. Recently, Laser Assisted Bonding (LAB) technology has emerged as an excellent solution to address the disadvantages of temperature uniformity and high pressure in the TC-NCF flip-chip bonding process [Ref. 1–2]. In this study, a Laser Non-Conductive Paste (NCP) is introduced and applied to the flip-chip process for fine pitch solder bump devices using the LAB process.