MIT

"This kind of team spirit in sharing hardship moved me, but it also brought immense pressure. Besides the operators, the foremen even more often asked what could be improved. Production director James Reese appeared on our production line every day, paying special attention to the progress of yield. Reese was one year older than I was, with an MIT bachelor’s degree in electrical engineering and a Harvard MBA. He quickly became a good colleague and good friend of mine. At that time, the nearly seventy of us were producing almost all scrap every day, yet every week he still wanted to add a few more people. I didn’t understand and argued with him. He said we should first hire enough operators and train their basic skills; once the yield made a breakthrough, we would have large quantities of product. Later developments proved he was right. A few months later the yield leapt forward, and we already had enough well-trained operators on the line. So in a short time, we not only made up the deliveries that should have been made but were not during the low-yield period, we also smoothly met IBM’s rapidly increasing demand."

"I dug out the heat transfer textbook I had studied at MIT and did some rough calculations, and found that my concern was correct. So over the next few days, I tried an indirect heating method: not letting the soldering tool directly contact the electrode, but only letting it contact the copper wire, using copper’s high thermal conductivity to melt part of the electrode and complete the soldering. My method was slower than the original, but the likelihood of disrupting the transistor’s internal chemistry should be lower than with the original method, so the final yield should be higher. After I myself became proficient in operating my soldering method, I began training the two most experienced operators. After one or two days, their soldering speed using the new method had reached 80–90% of the original method. We accumulated several hundred transistors soldered using the new method and compared the yield with another group of transistors soldered using the original method. Sure enough, the yield of the new method was noticeably higher than that of the original method. My supervisor came over to take a look, and the production manager also came to see it, and even sat down and asked me to teach him the new soldering method. A few days later, the entire production line switched to my method."