Wafer surface contamination metrology by VPD-TXRF
Measurement of ultra-trace elemental surface contamination
- Accepts 450 mm and 300 mm wafers
- Wide range of analytical elements (Na~U)
- Light-element sensitivity (for Na, Mg, and Al)
- Single target 3-beam method and XYθ stage are unique to Rigaku, enabling highly accurate ultra trace analysis over the entire wafer surface
- Integrated, fully-automated VPD preparation for highest sensitivity
- 1E7 atoms/cm² detection limits
- Import measurement coordinates from defect inspection tools for follow-up analysis
- Multitasking: simultaneous VPD and TXRF operation for highest throughput
TXRF analysis can gauge contamination in all fab processes, including cleaning, litho, etch, ashing, films, etc. The TXRF-V450 can measure elements from Na through U with a single-target, 3-beam X-ray system and a liquid nitrogen-free detector system.
The TXRF-V450 includes Rigaku's patented XYθ sample stage system, an in-vacuum wafer robotic transfer system, and new user-friendly windows software. All of these contribute to higher throughput, higher accuracy and precision, and easy routine operation.
Integrated VPD capability enables automatic VPD preparation of one wafer while a TXRF measurement is made on another wafer for the highest sensitivity and high throughput. VPD-TXRF eliminates the operator variability that may occur with ICP-MS, and VPD-TXRF can be completely controlled via factory automation. VPD recovery from selected areas, including the bevel area, is available.
Optional Sweeping TXRF software enables mapping of the contaminant distribution over the wafer surface to identify "hot spots" that can be automatically re-measured at higher precision.
Optional ZEE-TXRF capability overcomes the historical 15mm edge exclusion of original TXRF designs, enabling measurements to be made with zero edge exclusion.
Optional BAC-TXRF capability enables fully-automated front-side and back-side TXRF measurements of 450 mm wafers with non-contacting wafer flipping.
|Technique||Total reflection X-ray fluorescence (TXRF) w/ vapor phase decomposition (VPD)|
|Benefit||Measurement of ultra-trace elemental surface contamination; 1E7 atoms/cm² detection limits|
|Technology||Automatic VPD preparation, three-beam excitation and automatic optics alignment|
|Core attributes||Automatic VPD, rotating-anode X-ray source, XYθ sample stage , liquid nitrogen-free detector, accepts 450/300 mm wafers|
|Core options||GEM-300 automation software for full factory automation, SP-TXRF capability enables mapping of the entire wafer surface, ZEE-TXRF capability enables measurements to zero edge exclusion, BAC-TXRF capability enables fully-automated front-side and back-side measurements|
|Computer||Internal PC, MS Windows® OS|
|Mass||n/a (core unit)|
|Power requirements||3Ø, 200 VAC 50/60 Hz, 125 A|