There are at least four potential lithographic pathways to the manufacture of large panels with the required RDL resolution of 2 µm half pitch or better.
- Use of flat panel display (FPD) technology. The CANON MPAsp-E903T is a wide-field lithographic system capable of resolving 1.2µm line and space features across Gen6 glass panels that measure 1500 x 1850mm.
- Maskless imaging by EV GROUP achieves 2µm line and space resolution with no substrate size limitation. This equipment may be too slow for volume production but could be used to prototype microelectronic modules.
- Use of SHINKO technology for producing finely patterned redistribution layers on organic substates, following their i-THOP substrate structure.
- If tiles are matched with reticle-sized images, they can be step-and-repeated across large size panels. If the tiles implement independently operable clusters of components, they may require a minimal set of interconnections between them. The interconnections may be created by stitching, wherein overlay errors of the order of 10µm may be acceptable.