Kenzo Hatada

LED array modules by new technology microbump bonding method

An LED array module was developed by using the microbump bonding method by which the electrodes of LSI chips and circuit substrate are press-bonded by utilizing the shrinkage stress produced in a light setting insulating resin. The LED array module has a resolution of 400 DPI, and is constructed by face-down mounting of 54 each of the LED chips and driver LSIs on a glass substrate. These LED chips, having an electrode pitch of 63.5 mu m, are disposed on the glass substrate at a pitch of 10 mu m. A dedicated bonder was developed for this assembling work. A report on the LED array module assembling process and the construction of a bonder is presented. >

Improvement of Coupling Efficiency for Passive Alignment of Stacked Multifiber Tapes to a Vertical-Cavity Surface-Emitting Laser Array

High-efficiency coupling of stacked multifiber tapes to a vertical-cavity surface-emitting laser (VCSEL) array is demonstrated. Three fiber tapes, each of which includes four multimode fibers, are coupled to a 4 x 3 VCSEL array simply by inserting fibers into guiding holes fabricated on the back side of the substrate. Mirrorlike smooth floors of the holes are formed by electron cyclotron resonance reactive ion beam etching, which results in great improvement of coupling efficiency. The average measured coupling efficiency is 81.3%.

New Film Carrier Assembly Technology: Transferred Bump TAB

Conventional tape automated bonding (TAB) uses IC chips with gold bumps, where gold bumps are formed on the aluminum bonding pads of the IC chips by metal evaporation, photoetching, and gold plating. The bumps of metal multilayer have to be formed directly on the IC chips in the conventional TAB method, and this necessitates a number of complicated processes and equipments. With the newly developed film carrier assembly technology, the bumps are prepared separately on a substrate and are transferred and bonded on the finger lead ends beforehand, therefore the assembly of IC chips can be made very simple and the assembly cost reduced.

New solderless connection technology using light-setting insulation resin

A new solderless connection technology using light-setting insulation resin has been developed. This makes possible fine-pitch and short length connection between the FPC (Flexible Printed Circuit) and the electrodes of an electronic device. An FPC is attached by the adhesive force of the light-setting insulation resin. This technology has been applied to a thin-film magnetic head, and realized ultra fine connection, i.e. a connection pitch of 75 /spl mu/m (present ratio 1/2) and a connection length of 250 /spl mu/m (present ratio 1/10).<<ETX>>

Examination on the 3D Assembly Module

We have presented R&D progress of our Three Dimensional Assembly Module called TZ-CSP (Tape Z-axis Chip Size Package) in our previous papers. In this presentation, we would like to present you improvement in assembly techniques and refinement in design parameters we have made in order to mass-produce TZ-CSP. Specific improvements are made to the key processes in TZ-CSP production such as tooling method and connecting method for inter-layer connection lead. Also, we have evaluated status of further functional improvements caused by SIP (System In Package) and Lead free solder. We also would like to present you the concept of trend towards SIP.