LowTemp™ Laser-Initiated Debonding

The laser debonding process being developed at EVG is based on excimer lasers, operating at either 308 nm or 248 nm wavelengths. In this spectral range, standard glass carriers still offer high transmission, keeping carrier cost low. In contrast to laser induced thermal debonding, the ultraviolet light emitted by excimer lasers is absorbed within a few hundred nm right at the glass/adhesive interface, thereby leaving the thin wafer entirely unaffected. Furthermore, the ultraviolet light from the excimer laser debonds primarily through photochemical means, directly breaking chemical bonds in the adhesive layer. Laser debonding enables very high throughput.

EVG Laser Debonding Technology Features:

  • No thermal stress subjected to the device wafer
  • Single adhesive layer technology, requiring no additional release layer application for lowest cumulated cost
  • High-throughput capability using field-proven excimer laser technology
  • High thermal resistance up to 350°C
  • Multiple thermoplastic adhesives feature laser debonding capability

 

Paper "Laser debonding enables advanced thin wafer processing"

Click on the thumbnail to read our joint paper with Coherent, published in the January 2013 issue of SST.

WaferDebondingArticle-1

Key process steps schematic:

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