Sachem reveals advancements in TSV silicon etching
Sachem has released "Reveal Etch," a wet chemistry designed to enable a single-step silicon etch / TSV reveal process.
Sachem and Solid State Equipment, LLC (SSEC) developed the process for this chemistry and optimised its use in a single-wafer processor.
Sachem Associates Yongqiang Lu, Sian Collins, Kevin McLaughlin, and Craig Allen, in conjunction with SSEC Associates Laura B. Mauer, John Taddei, and Ramey Youssef, jointly issued a technical paper on a new wet process alternative to the polish / plasma etch TSV reveal process.
SSEC and Sachem have worked on this new chemistry since early 2013. In February of 2014, the two companies produced a technical paper.
SSEC set out to further optimise its process chemistries by working with Sachem to develop a proprietary aqueous chemistry that contains no potassium and is residue free. Not only does this new chemistry address many issues limiting wet processing usage, but there are significant cost savings with the elimination of the extensive KOH residues clean step.
"The Sachem Reveal Etch chemistry is a key component to our TSV Revealer configuration on the latest SSEC platform called WaferEtch," states Erwan Le Roy, Marketing Vice President of SSEC. "After years of dedicated R&D for this 2.5D/3D application, we enabled the lowest cost-of-ownership equipment by integrating all the key components in one single tool - silicon thickness metrology for accurate end pointing determination, wet etch with a spin-etch chemistry to avoid using separate CMP equipment, a final etch with the Reveal Etch chemistry to uniformly expose the TSVs and wet cleaning."
"Sachem's developmental reveal etch chemistry combines our core capability in formulation, extensive knowledge of silicon etching and our high-purity expertise. Our solution optimises etch rate and surface roughness," stated Kevin McLaughlin, Global Electronic Materials Market Manager at Sachem, Inc. "We have taken a significant step forward in enabling the TSV process by combining our expertise with that of SSEC," says McLaughlin.
