Study Of Hot Press Soldering Process

Recently TFT-LCD industry has been developed very quickly in China. Among them, LCD module manufacturing has formed scale industry in Yangtze River Delta and Pearl River Delta. And customer demand of middle-size and small-size LCD has been continued to grow. The products are widely applied in consumer electronics marketing including digital camera, mobile phone, portable DV, Car-carrying GPS, digital photo frame, pocket notebook computer. Because LED is getting better in optical performance, excellent in energy saving and useful time, LED has taken the place of CCFL as the backlight source in many middle-size and small-size LCD module.Hot press soldering in this paper is a useful process to connect LED backlight circuit and LCD signal circuit. Stable and high efficient hot press soldering process is necessary for raising module yield and assuring product quality.In this paper, first briefly introduces the soldering basic theory (reflow soldering), and then illustrates the technique of hot press soldering process. In the following section we achieve the best recipe of process parameters (temperature, time, pressure) through Taguchi Methods. In the end of the paper we study the top3 defects (weak-soldering, solder overflow, solder pad broken), and find out the solutions for these problems.In conclusion, we know for getting good quality in soldering, we have to deal with every step well including improving all relative machine, process parameters, jig and product design.Despite achieving good performance, this subject applied for a patent about solder pad circuit design, and this patent has passed the company verification.