In recent years, as mobile equipment such as cellular phones and PDAs become drastically higher performance and downsized, semiconductor devices are rapidly becoming more integrated and higher speed. As a result of high integration, the pitches of electrode pads in chips are becoming smaller than 100 µm. In some devices, pad pitches are as small as 40 µm.
Zhimou XuShaowei HeXong LiShangbao WangXinjian YiKun LianSheng Liu
Kazuyoshi IdeiKouichi ItoigawaTakeshi KitadaniYoshitaka SawaKenji YamashitaDaiji NodaTadashi Hattori
Zhijian ZhouWeirong NieZhanwen XiXiaofeng Wang