DATA STORAGE

Highlights

  • Diverse offering for both production and FA
  • Fast defect inspection for rough substrates
  • Metrology on chamfer width and angle, and wall
  • Sub-nanometer defect and pit classification

EDGE INSPECTION

The ZETA-20CM is designed to inspect the disk edge chamfer profile completely, from top surface to sidewall



MULTIPLE MEASUREMENTS

  • Full Chamfer Profile, top edge to sidewall
  • Chamfer Roughness
  • Chamfer and Sidewall Defect Inspection
  • ID and OD Diameter and Concentricity

ACCURATE, FAST, AND USER FRIENDLY

  • <40 sec per scan at each site
  • Automated multi-site measurements
  • Custom recipes for critical parameters

MATERIAL AND SAMPLE INDEPENDENT

  • Both glass and metal disks
  • All diameters and thicknesses
  • From very high to very low roughness

A NEW WAY TO LOOK AT THE CHAMFER

The ZETA-20CM uses the proven technology of the Zeta Instruments family

of Non-contact Optical Profilers to provide detailed 3D scans and roughness analysis on any part of the disk surface.



Poor chamfer geometry steals valuable real estate from the data zone. Analyzing the chamfer angle and width is crucial for optimizing the polishing process.

SILENT KILLERS: ROUGHNESS AND DEFECTS

For the first time, it is possible to examine roughness and defects on the side wall in a systematic way.

Subtle edge process variations may have unexpected effects on the finished product – but without reliable metrology, characterization is very difficult.

SYSTEM INFORMATION

The Zeta-20CM uses 4 axis motorized stage (X-Y-Roll-Theta) to position the disk for each measurement. Automated Recipes acquire the data and report the statistics for each measurement. Automated Sequences chain recipes together to create powerful combinations of measurements, making process control faster and more repeatable. The system’s ID clamps accommodate disk diameters from 65 mm up to 95mm with an inner diameter of 20 mm or 25mm. Available OD clamps enable the inspection of ID chamfer. The Ring Light equipped objectives allow the inspection of the side wall of the disks for defects such as particles and scratches as well as the measurement of the disk’s outer diameter, inner diameter and concentricity. Stitching option can be used to create a full 3D view of the side wall and chamfer region of the disk


DEFECT INSPECTION

The ZetaScan uses a violet laser diode to generate a linear scan.

The 405nm wavelength provides a high sensitivity to sub-micron defects such as particles and pits. Multiple channels of data are acquired simultaneously to ensure a fast scan as well as clear defect classification.

  • Scatter is Zeta’s proprietary enhanced scatter detection mode that enables pit-particle separation and accurate defect classification
  • ZetaScatter is the typical scattered light acquired by most defect inspection tools. While this channel is very sensitive to particles, additional information is required for defect classification.
  • Topography channel enables the detection of surface roughness variation as well as large area scratches and other topographic defects that do not scatter.
  • Specular reflected light channel enables detection and classification of thin film defects, adding another powerful detection and classification mechanism
  • Other… give us your inspection challenge. Zeta’s development team is continuously innovating new modes of defect detection.

IMPROVED PROCESS FEEDBACK

The ZetaScan can handle rough cut, polished, opaque or transparent substrates as well as epi wafers and thin film coated substrates. The flexible optical architecture enables the inspection of wafers, substrates as well as completed devices such as smart phones and tablets. This unique capability is unparalleled in the industry. Combined with the high throughput, it also means that the same tool can be used to inspect samples from multiple process steps, thus improving process feedback while keeping inspection costs low.



Multi-Mode Inspection

The same defect has different signatures in the various detection channels



Disk Defect Mapping

Micropit clusters (dark spots) on a rough polish disk substrate

Scuff Mark

A short Scuff Mark on a NiP disk as seen in the Specular image

Micro-Pit on a Disk

The topography image of a Micro-Pit and the surrounding disk texture

Precision Scribe

A precision diamond scribe can be used to mark defects for further analysis





Micro-­Pit vs Particle

FAST FULL WAFER DEFECT MAPPING

The linear scanning motion of the incident beam is combined with the lateral motion of the wafer to quickly generate the full wafer defect map. This type of scan is faster, more stable and less sensitive to vibration as compared to other ‘helical’ or ‘spiral’ scan based tools.

AUTOMATED DEFECT CLASSIFICATION

The multiple detection channels can be used for easy defect classification. In the example shown below, all the particles can be detected in the Scatter channel. Only the very large particles are seen in the ZetaScatter channel. Pits are clearly visible in the ZetaScatter, but cannot be detected in the Scatter channel. Thus, the multi-mode optical design is leveraged to provide accurate defect classification.

Zeta-20CM

Product Info»