A method and apparatus for use in forming pre-positioned solder bumps (104) on a pad arrangement (100) of a substrate (101) include placing a predetermined pattern (306) of solder preforms (304) in contact with a meltable adhesive fluxing agent (302) on a carrier tape (402), and then heating the fluxing agent (302) to melt it Next, the fluxing agent (302) is cooled to resolidify it, thereby securing the solder preforms (304) to the carrier tape (402) The carrier tape (402) is then aligned over the pad arrangement (100) and the solder preforms (304) are transferred to the pad arrangement (100) by heating the solder preforms (304) to form the solder bumps (104) in the predetermined pattern (306)

Method and apparatus for use in forming pre-positioned solder bumps on a pad arrangement

A chemical batch bumping method is suggested both for Flip-Chip and TAB (tape automated bonding) appli- cations Several suggestions from earlier studies by other authors are referred and commented. Experiments with a selective Ni/Au bump structure have been carried out in a prototype processing line. The initial results confirm that this method has low capital, material and labor cost As no die specific tooling is required the process will have fast tum-around time and potential even for low vol- ume low cost wafer bumping, as well as for mass production.

http://ieeexplore.ieee.org/iel3/5087/13879/00639289.pdf

Towards Low Cost High Density Bumping

The effects and implications of current developments in interconnection technology on print and fire thick film hybrid manufacture are discussed. Particular emphasis is given to the fact that in many cases new techniques complement rather than compete with film hybrids. Alternative substrates, semiconductor packaging, semicustom integrated circuits, surface mount technology and polymer thick film are all included in the paper. Conclusions are drawn which indicate that although these technologies are all of crucial importance they will not replace current thick film technology.

Future Trends and Developments in Circuit Technology

Demanding technical requirements of thin film electroluminescent display modules and hard competition in electronic display markets set boundaries for the setting of goals in the development of an extremely thin display module. To meet the targets the problems of electronic packaging concepts had to be considered from the point of view of total optimisation. As a result, a packaging concept was developed which had an influence on all design decisions starting from the end user's requirements and extending to the selection of a special semiconductor manufacturing process. A set of customised high voltage integrated driving circuits was developed. High density interconnection problems were solved by the tape automated bonding of semiconductors and a single‐sided two‐layer polymer thick film circuit board. Throughout the assembly process surface‐mounted components and reflow soldering methods were applied to form a large area printed polymer hybrid module. Viable volume production methods for a flat dot‐matrix display could be suggested.

A. Aintila

Papers

Packaging of Dot‐matrix Electroluminescent Display Module