150mm Through Substrate Interconnect Conversion One Year Later

L.S. Klingbeil, K.L. Kirschenbaum, C.G. Rampley, D. Young
Motorola Semiconductor Products Sector

The momentum for III-V technologies with through substrate vias continues to increase making a 150mm wafer size conversion inevitable to meet increased demands. The seven month conversion at Motorola's CS-1 was rapid and cost effective because most of the equipment set was 150mm compatible and only some additional capacity installation was needed.

The fab conversion was not without process related hurdles, including the thousand plus wafers per week run rate within the through substrate interconnect module. Maintaining a competitive wafer cost requires the minimization of resource costs which increased with the 150mm process. The increase in cost is largely attributed to increased labor force and increased sapphire mounting substrate costs. Equipment limitations processing 150mm mounted wafers and greater process sensitivity created technical challenges that required significant attention. Establishing a low cost, high volume capable process required a balance of these two constraints.