Christopher L. Tessler

Polymer ablation with a high-power excimer laser tool

Abstract A high-power excimer laser projection ablation tool and process in a manufacturing line is described. The light source is a 150 W XeCl (308 nm) gas laser. The projection ablation unit is very similar to that of a photo expose tool and comparisons will be made. The laser, beam delivery system, projection optics, beam homogenization, system accuracy (overlay), tool, process, operation, control, and system reliability will be discussed.

Characterization, setup, and control of a manufacturing laser ablation tool and process

This paper is a description of the ablation of polyimide with an excimer laser ablation tool in a manufacturing line. The light source is a 150 watt, XeCl (308 nm) gas laser. Two methods of ablating via patterns with the laser tool (full-chip and scan modes) will be discussed, in addition to the tool, set-up, operation and tool/process control.

End-to-End Integration of a Multi-die Glass Interposer for System Scaling Applications

The processes key to enabling 3D manufacturing, namely, bond, backgrind, and through silicon via (TSV) reveal, are extended for 300 mm glass substrates to fabricate a heterogeneous, multi-die, 2.5D glass interposer. Based on an existing silicon interposer offering, the glass interposer is comprised of multi-level “device” side copper wiring, with line space (L/S) of ≤ 2.5 μm, built using damascene techniques, a 55 μm glass core with through glass vias (TGVs), and multiple UBM levels finished with tin silver (SnAg) C4 bumps. The 300mm TGV wafers are processed on existing silicon wafer manufacturing equipment following established, integrated silicon process flows. Once fully processed, the glass wafers are diced, and the interposer joined to a ceramic carrier by mass reflow. Sub-assemblies are then underfilled, the top die attached, and lidding completed. The final assemblies are tested to evaluate performance of chip to chip interconnects, chip-to-package (through interposer) interconnects, and chip-to-PCB (through interposer and package) interconnects. Results of loss vs frequency measurements are compared, for the glass interposer against the existing silicon interposer results.