Gold Stud Bumps Flip-Chip Bonded onto Copper Electrodes with Titanium and Silver Layers |
| |
Authors: | Cheng-Li Chuang Jong-Ning Aoh Qing-An Liao Chun-Chieh Hsu Shi-Jie Liao Guo-Shing Huang |
| |
Affiliation: | (1) Department of Occupational Safety and Health, Chung Shan Medical University, No. 110, Sec. 1, Chien-Kuo N. Road, Taichung, 402, Taiwan, ROC;(2) Department of Mechanical Engineering, National Chung Cheng University, 168 University Road, Minhsiung, Chiayi, 621, Taiwan, ROC;(3) Department of Packaging Equipment, Laser Application Center, Industrial Technology Research Institute South Branch, No. 8, Gongyan Road, Liujia, Tainan, 734, Taiwan, ROC |
| |
Abstract: | The purpose of this study was to develop the thermosonic flip-chip bonding process for gold stud bumps bonded onto copper electrodes on an alumina substrate. Copper electrodes were deposited with silver as the bonding layer and with titanium as the diffusion barrier layer. Deposition of these layers on copper electrodes improves the bonding quality between the gold stud bumps and copper electrodes. With appropriate bonding parameters, 100% bondability was achieved. Bonding strength between the gold stud bumps and copper electrodes was much higher than the value converted from the standards of the Joint Electron Device Engineering Council (JEDEC). The effects of process parameters, including bonding force, ultrasonic power, and bonding time, on bonding strength were also investigated. Experimental results indicate that bonding strength increased as bonding force and ultrasonic power increased and did not deteriorate after prolonged storage at elevated temperatures. Thus, the reliability of the high-temperature storage (HTS) test for gold stud bumps flip-chip bonded onto a silver bonding layer and titanium diffusion barrier layer is not a concern. Deposition of these two layers on copper electrodes is an effective and direct method for thermosonic flip-chip bonding of gold stud bumps to a substrate, and ensures excellent bond quality. Applications such as flip-chip bonding of chips with low pin counts or light-emitting diode (LED) packaging are appropriate. |
| |
Keywords: | Gold stud bump flip-chip bonding copper electrode titanium barrier layer silver bonding layer high-temperature storage test |
本文献已被 SpringerLink 等数据库收录! |
|