Diamond Wire

Diamond Wire Wear Inspection

The Resonance Vibrations (RV) method was developed for non-destructive real-time inspection of Diamond Wire (DW) quality. The in-line RV-DW sensor induces small vibrations in a DW segments during the wire motion in a wafer cutting tool and measures its resonance characteristics to assess wire quality and DW wearing stage. Core element of the RV-DW sensor is a non-contact probe. The RV data acquisition and analyses are performed within tens of milliseconds, matching the speed of the modern wafering process. The sensor is computer controlled with Windows based software and convenient Graphical User Interface.

RV vs. Optical

Wafer producers are exploring a high resolution optical imaging to assess DW quality by detecting loss of material and tracking the DW wearing stage.

Optical method disadvantages:

  1. Only surface diagnostics of the wire components, while the DW wearing is also affected by degraded sub-surface layers (Ni, Cu.)
  2. Algorithm for real-time DW optical inspection generates high uncertainties caused by irregularities in the diamond particles.
  3. Wafering process creates chemical residues that requires frequent maintenance of the optical hardware.

RV-DW senor:

  1. Ensures inspection of the DW bulk and surface properties (both diamond particle loss and sub-surface metallization) during wafering.
  2. Reduces scrap material by eliminating DW breakage which leads to yield reduction and product cost increase.
Resonance Vibrations
Yes / No
Bulk DW diagnostics
Cost and maintenance

Keyence image
Microscopic images (Keyence, VHX-6000) of new (right) and used (left) 70 microns core DW samples
RUV measurements
The RV data measured by the RV-DW sensor shows clear shift of the resonance frequency between new and used diamond wires

RV-DW Sensor Specifications

  • Minimum diamond wire diameter - 60 microns
  • Maximum DW speed - 30 meters per second
  • Maximum temperature – 60C
  • Accuracy of diamond wire wear – 10%

Additional details are available in the publications section.