Chip Shooter to Enable Fine Pitch Flip Chip

Chip shooters are well known placement technology for low precision, simple package components such as resistors and capacitors in electronic packaging. Widely-used chip shooters are capable of placing component sizes as low as 01005 (200 × 400 μm). With the application of System in Package (SIP) module packaging, die bonder technology for flip chip connection faces the loss of line switching processing time, the decrease of Chips per Hour (CPH) and process risks. The drive for new chip shooter applications such as flip chip die placement necessitates more focus on high accuracy chip shooter placement to enable fine pitch flip chip die on laminate beyond conventional component placement. In this paper, we introduce a chip shooter placed flip chip die with fine pitch solder interconnects on a laminate substrate. The challenges to enable reliable fine pitch flip chip with chip shooter will be discussed from all perspectives including: chip shooter placement accuracy, assembly process capabilities, and comparison between solder bumps and copper pillar bumps. We enable fine pitch flip chip interconnect at 120 μm pitch with ±25 μm alignment accuracy chip shooters, and passed process cornering check as well as reliability tests.