| Summary: | 碩士 === 國立臺北科技大學 === 工業工程與管理研究所 === 92 === The joints of assembly function as the supply of power and transform for signal of electronic devices. The assembly interface and soldering techniques comprise diverse joint types in which the printed circuit board of assembly is the most important one which can be the central point of the system. The wettability of the IMC（Intermetallic compound）formation between electronic components, printed circuit board, and solder alloy especially directly affects the solder point quality and reliability of instrument used.
This thesis assessed the wetting behavior and solderability between different shapes of electronic components and various metal electroplating material. This study employs wetting balance method to measure the wetting data under discrepant processing environment such as steam aging, solder temperature, wetting time, flux type, dip speed, dip depth, and Sn-Pb / lead free solder (60Sn40Pb/ Sn3.0Ag0.5Cu), and to estimate the wetting properties (qualitative) and solderability (quantitative) .
The Taguchi methods and design of experiment were employed to determine interrelationships between steam aging, solder temperature, flux type, dip depth, wetting time, and determine optimal process condition.
Experimental results demonstrate the wettability of golden-plated terminal is better without steam aging, and forceful with cleaning the surface by flux type. Furthermore, the size (1206) of MLCC is the same while the terminal electroplating and conformation is diverse and electrode surface processing is altered（Sn/Ni/Ag ,Ag+Pt）to operate the tests. The results demonstrate that the terminal with solder globule method is better than with solder bath method. However, concerning the wetting time, the solder bath method is better than the solder globule method. In our research, these optimal wetting properties must be obtained under low dip speed (1 mm/ sec), no oxidation (no steam aging), enough wetting time, and with cleaning the surface by flux type (SM/NA). Besides, the terminal solderability is particularly affected by melting point of different solder alloys. As a result, before application of electronic devices in soldering processing, we must carefully consider the applicability and discrepancy of reflow soldering and wave soldering process.
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