Weir PW Analysis of wafer-chuck influence on features Dataset:80_D2_1_2 Features: Device: x5 1:1 / Level: ASML AMD T nm LotName No:80D2_1_2 03-Nov-03 TEA Systems Corp. 65 Schlossburg St. Alburtis, PA November 12, 2003

TEA Systems Corp. Confidential November 2003Weir PW - Wafer Chuck Influence on CDsPage -2- Investigation Each wafer chuck provides kinematic support for the wafer on 3 pins ?Located at an approximate radius of 30 mm from wafer center ?Separated by 60degrees ?Pin is 2 mm in diameter Wafer is then suspended above the chuck by approximately 75 um.

TEA Systems Corp. Confidential November 2003Weir PW - Wafer Chuck Influence on CDsPage -3- Raw data measured Scatter tool data used: ?Nanometrics Weir PW analysis Data included: ?BCD ?TCD ?SWA ?T3 (Resist) ?T2 (BARC) Die Size is (25,28)mm Locations on Field Locations on Wafer

TEA Systems Corp. Confidential November 2003Weir PW - Wafer Chuck Influence on CDsPage -4- Wafer Modeled BARC Wafer systematic errors have been removed.

TEA Systems Corp. Confidential November 2003Weir PW - Wafer Chuck Influence on CDsPage -5- BARC: Wafer cross-section Examination of cross-section as shown Notice definite step at wafer 30 mm diameter Potential pad site

TEA Systems Corp. Confidential November 2003Weir PW - Wafer Chuck Influence on CDsPage -6- BARC radial Step occurs outside of pin radius = 30 mm.

TEA Systems Corp. Confidential November 2003Weir PW - Wafer Chuck Influence on CDsPage -7- Photoresist Wafer-systematic errors have been removed ?Mean value of nm also removed Three points may show as slightly shifted contacts. ?Note circled points

TEA Systems Corp. Confidential November 2003Weir PW - Wafer Chuck Influence on CDsPage -8- BCD – Wafer & Average field removed Plotting Bottom CD after removal of: ?Wafer aberrations ?Average field. 3 potential locations of wafer pads

TEA Systems Corp. Confidential November 2003Weir PW - Wafer Chuck Influence on CDsPage -9- Top CD variation after mean field is removed Examine the CD variation after having remove: ?Wafer systematic errors and ?The average field.(reticle)

TEA Systems Corp. Confidential November 2003Weir PW - Wafer Chuck Influence on CDsPage -10- Top CDs and radius Notice dip located at the 30 mm radius From here on we will restrict the analysis radius to 94 mm ?Excludes the bad data points shown at the edge-bead.

TEA Systems Corp. Confidential November 2003Weir PW - Wafer Chuck Influence on CDsPage -11- Conclusion & discussion points BARC, Photoresist and Bottom CDs suggest there is an effect occurring at the 30 mm wafer radius. ?Bottom CD and photoresist strongly suggest the presence of 3 sites at the radius and spacing suggested by the wafer-chuck pins. ?BARC has a radial height variation that also suggests something strong happening below this 30 mm radius. Top CD shows some reaction but it is not as apparent as with the previous variables discussed. SWA does not show the effect

TEA Systems Corp. Confidential Analysis Slides presented as backup data

TEA Systems Corp. Confidential November 2003Weir PW - Wafer Chuck Influence on CDsPage -13- Raw BARC Thickness (T2)

TEA Systems Corp. Confidential November 2003Weir PW - Wafer Chuck Influence on CDsPage -14- Wafer Modeled BARC Wafer systematic errors have been removed.

TEA Systems Corp. Confidential November 2003Weir PW - Wafer Chuck Influence on CDsPage -15- BARC: Wafer cross-section Examination of cross-section as shown Notice definite step at wafer 30 mm diameter Potential pad site

TEA Systems Corp. Confidential November 2003Weir PW - Wafer Chuck Influence on CDsPage -16- BARC radial Step occurs outside of pin radius = 30 mm.

TEA Systems Corp. Confidential November 2003Weir PW - Wafer Chuck Influence on CDsPage -17- Weir PW Measurement of Bottom Raw – Bottom CDs

TEA Systems Corp. Confidential November 2003Weir PW - Wafer Chuck Influence on CDsPage -18- Wafer Modeled Bottom - CD

TEA Systems Corp. Confidential November 2003Weir PW - Wafer Chuck Influence on CDsPage -19- Histogram after wafer aberrations are removed

TEA Systems Corp. Confidential November 2003Weir PW - Wafer Chuck Influence on CDsPage -20- BCD – Wafer errors removed Data removed: ?Wafer systematic ?Mean Bottom CD offset = nm Display is dominated by the signature of the reticle.

TEA Systems Corp. Confidential November 2003Weir PW - Wafer Chuck Influence on CDsPage -21- BCD – Wafer & Average field removed Plotting Bottom CD after removal of: ?Wafer aberrations ?Average field. 3 potential locations of wafer pads

TEA Systems Corp. Confidential November 2003Weir PW - Wafer Chuck Influence on CDsPage -22- Top CD; Wafer Model Offset is not plotted Well now remove these systematic errors.

TEA Systems Corp. Confidential November 2003Weir PW - Wafer Chuck Influence on CDsPage -23- Top CD variation after mean field is removed Examine the CD variation after having remove: ?Wafer systematic errors and ?The average field.(reticle)

TEA Systems Corp. Confidential November 2003Weir PW - Wafer Chuck Influence on CDsPage -24- Top CDs and radius Notice dip located at the 30 mm radius From here on we will restrict the analysis radius to 94 mm ?Excludes the bad data points shown at the edge-bead.

TEA Systems Corp. Confidential November 2003Weir PW - Wafer Chuck Influence on CDsPage -25- SWA Wafer Model SWA variation across systematic error model Offset of 86.1 deg. Is not included.

TEA Systems Corp. Confidential November 2003Weir PW - Wafer Chuck Influence on CDsPage -26- SWA residuals Removed ?Wafer model ?Average Field Each site is averaged & then removed. SWA exhibits only the variation caused by the start and top of the exposure scan. Does not show any reaction at 30 mm radius

TEA Systems Corp. Confidential November 2003Weir PW - Wafer Chuck Influence on CDsPage -27- Photoresist Wafer-systematic errors have been removed ?Mean value of nm also removed Three points may show as slightly shifted contacts. ?Note circled points