상세정보
학술지
Fine-Pitch Solder on Pad Process for Microbump Interconnection
- 발행일
- 201312
- 출처
- ETRI Journal, v.35 no.6, pp.1152-1155
- ISSN
- 1225-6463
- 출판사
- 한국전자통신연구원 (ETRI)
- 초록
- A cost-effective and simple solder on pad (SoP) process is proposed for a fine-pitch microbump interconnection. A novel solder bump maker (SBM) material is applied to form a 60-μm pitch SoP. SBM, which is composed of ternary Sn3.0Ag0.5Cu (SAC305) solder powder and a polymer resin, is a paste material used to perform a fine-pitch SoP through a screen printing method. By optimizing the volumetric ratio of the resin, deoxidizing agent, and SAC305 solder powder, the oxide layers on the solder powder and Cu pads are successfully removed during the bumping process without additional treatment or equipment. Test vehicles with a daisy chain pattern are fabricated to develop the fine-pitch SoP process and evaluate the fine-pitch interconnection. The fabricated Si chip has 6,724 bumps with a 45-μm diameter and 60-μm pitch. The chip is flip chip bonded with a Si substrate using an underfill material with fluxing features. Using the fluxing underfill material is advantageous since it eliminates the flux cleaning process and capillary flow process of the underfill. The optimized bonding process is validated through an electrical characterization of the daisy chain pattern. This work is the first report on a successful operation of a fine-pitch SoP and microbump interconnection using a screen printing process. © 2013 ETRI.
- KSP 제안 키워드
- Bonding process, Capillary flow, Cleaning process, Electrical characterization, Fine pitch, Oxide layer, Polymer resin, Printing method, Screen printing process, Si substrate, Solder On Pad