Ultrasonic wire bonding for semiconductor

Abstract

Abstract PURPOSE:To achieve full automation of a bonding work by a method wherein reference points are established on pellets fixedly pre-positioned ona lead frame and the fixed points are sensed by photoelectric scanning and their deviation as to positioning is determined and corrected. CONSTITUTION:A lead frame L with pellet S fixed thereon is positioned by a loader 1 properly on a positioning platform 2. A pre-set program rotates the positioning platform 2 gradually until a desired pad Sp and post Lp are in line with the Y axis. A heat 6 is then driven and a bonding work is accomplished. The reference positions A1 and A2 of two pads on the pellet S serve as fixed points and the deviation of actual positions a1 and a2 from the A1 and A2 is determined prior to bonding. The deviation is then inputted in a microcomputer that calculates the distance a stage 7 is to travel and the angle that the positioning platform 2 is to rotate for each set of Sp and Lp. The microcomputer thus adjusts bonding conditions and control the process. Even when each sample is located at a different position, the bonding work is performed automatically without manual adjustment.

Inventors

• 👤 Takeshi Hasegawa
• 👤 Akio Bando

Bibliographic Details