The Establishment of Incoming Test Criteria for Electrontic Materials - Solder Paste Testing and Evaluation

• Main Authors: Cheng-han Kao, 高正翰
• Other Authors: Chien-yi Huamg
• Format: Others
• Language: zh-TW
• Published: 1999
• Online Access: http://ndltd.ncl.edu.tw/handle/79097735067427658471

碩士 === 華梵大學 === 工業管理學系碩士班 === 87 === The increase use of Surface Mount Technology (SMT) in Printed Circuit Board (PCB) assembly is a result of the need for reduced weight, volume and cost in electronic packaging. Solder paste that includes solder particles and flux binder is applied on the copper pad (on the board) through stencil printing. Solder paste serves multiple critical purposes in the surface mount assemblies. The rheology is critical for the solder paste to transfer to the PCB through stencil apertures during stencil printing. Besides, solder paste contains the flux necessary for effecting soldering. It also acts as temporary adhesive to hold the component in place before soldering. Therefore, the quality of solder paste is essentially to contribute to quality of solder joint. The electronic packaging and SMT assembly have become one of the major industries in Taiwan. All major Taiwanese computer companies dominate the manufacturing of one third of total Notebook computers worldwide. To survive in this competing environment, these computer manufacturers have to continue improve their process capability, such as reduced manufacturing/material cost, increased assembly yield, and improved package reliability. A review with those major domestic assembly houses indicated that there is a lack of well-documented procedures that can be used for solder paste testing and evaluation as material incoming test. This research intends to establish a standard solder paste testing and evaluation procedure. Relevant test specifications were reviewed along with the determination of robust (and reasonable) testing parameters. Several types of solder paste commonly used in the packaging industry were evaluated through the use of Design for Experiments (DOE). The test results were provided to the industry as reference for improvement. Inference was drawn to improve the understanding of the material properties and assembly processes. This research has helped establish the infrastructure of solder paste evaluation procedure and eventually helped improve the assembly yield as well as package reliability.