Direct to Digital Holography [report]

P.R. Bingham, K.W. Tobin
2007 unpublished
In this CRADA, Oak Ridge National Laboratory (ORNL) assisted d i n e Corporation of Austin, TX in the development of prototype semiconductor wafer inspection tools based on the direct-todigital holographic (DDH) techniques invented at ORNL. Key components of this work included, development of the first prototype named the Visible Alpha Tool (VAT) that uses visible spectrum illumination of 532nm, assist in design of second prototype tool named the DUV Alpha Tool @AT) using deep UV (266nm)
more » ... p UV (266nm) illumination, and continuing support of d i n e in the development of higher throughput commercial tools. Statement of Objectives At the start of this CRADA, d i n e Corporation was a new company started with venture capital funding based on the DDH techniques. nLine had plans to develop four prototype tools based on direct-todigital holographic (DDH) techniques invented at Oak Ridge National Laboratory (ORNL). The first objective of this project was to develop, design, and fabricate a working engineering proof of principle DDH inspection tool. This i h t prototype used a laser in the visible spectra (532 nm) and is called the Visible Alpha Tool (VAT). The primary goals of the VAT development were to show that the DDH system works with improved optics (noise is significantly reduced) and that, through die-todie comparisons, defects on the order of -15Onm (depending on laser selected) can be detected in a reasonable time (about 1/2 day.) Some features of the VAT are a visible laser (532 nm), 1 Mpixel CCD camera, autofocus, manual wafer handling, automated wafer registration and image capture, and a low throughput rate.
doi:10.2172/932949 fatcat:jtcbxqth4vfcheyl6feqffw5la