Fluorine Atom Beam Hyper-Thinning of Silicon

We propose to develop a fluorine atom source for hyper-thinning "as-built" silicon wafers and separated integrated-circuit devices. This neutral-beam approach, based upon our fast atom sample tester (FAST) technology, does not produce high-energy ions; thus, it avoids the bombardment damage and the chemical complexity of plasma-assisted dry etching. The FAST apparatus will be reconfigured to yield an intermediate-energy high-flux fluorine atom beam; specifically, 1 to 10 eV, 10-16 to 10-17 atoms/cm-2-s. The beam will be diagnosed, process parameters will be determined, and operational maps will be constructed. Hyper-thinning of silicon substrates will be demonstrated, and the absence of both damage and surfgace residues will be verified. In collaboration with the Semiconductor Division of M/A COM, the fluorine FAST process will be assessed for production use. One or more device lines will be selected as the Phase II test-bed. The process flow charts will be modified to accommodate fluorine atom beam thinning, and changes in product yield will be estimated. The technical benefits and market advantages of the hyper-thin components in the proposed baseline technology will be projected. Finally, a business plan will be written, in order to evaluate the acquisition of the fluorine FAST process by M/A COM.