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As semiconductor manufacturing technologies advance, semiconductor manufacturing processes are becoming more and more sophisticated. Thus, how to maintain their feasible production yield becomes an important issue. As shown in Figure 1.12, during the product life cycle, the product yield (blue solid line) gradually rises up in the research‐and‐development (RD) phase and ramp‐up phase and then keeps steady in the mass‐production (MP) phase. On the contrary, the product cost (red solid line) continuously decreases during the production life cycle. If a company can improve its changing curves of yield and cost from the solid lines into their corresponding segmented lines, the company’s competitiveness would be enhanced effectively. This implies that rapidly increasing the yield in the RD phase to transfer products into the MP phase, and then assuring the yield in the MP phase while promptly finding out and resolving the root causes of yield losses is a feasible strategy for increasing the company’s competitiveness. However, no literature has proposed a systematic approach of enhancing and assuring production yield, which targets both the RD phase and the MP phase of the product life cycle.

Figure 1.12 Changing curves of yield and cost during the product life cycle.

Source: Reprinted with permission from Ref. [61]; © 2017 IEEE.

In the following, a five‐stage approach as shown in Figure 1.13 for enhancing production yield and assuring nearly ZD, taking a semiconductor bumping process as an illustrative example, is proposed.

Figure 1.13 Five‐stage strategy for increasing yield in RD/ramp‐up and MP phases of a manufacturing process.