Surfscan® Particle Counting (Surfscan)

Surfscan® Particle Counting
Excerpt of report printout for a standard 300mm silicon wafer from a Surfscan® Sp1 system.

Particle counting by Surfscan® (“Surfscan”) is an optical, non-contact surface characterization technique designed to accomplish rapid detection of particles and in some cases wafer defects.

It is one of the most common ways to quantify the number and size of particles dispersed across the surface of an unpatterned wafer (often called a blanket or monitor wafer).

  • Extremely fast, and optimized to accommodate serial wafer characterization
  • Identifies multiple wafer defect types: particle / point, scratch, haze
  • Particles must be embedded defects in unpatterned substrate
  • Lower limit of particle size determined by model of the system for SP1 it is 90 nm
  • Recipe must match type of wafer i.e. different for bare substrate versus oxide coated
Example Outputs
Instruments Used for Surfscan
KLA-Tencor Surfscan® SP1-TBi

KLA-Tencor Surfscan® SP1-TBi

  • Triple Beam illumination (TBi)
  • Provides Sensitivity, Repeatability, Surface Quality Measurements & Throughput Capabilities Required for 0.18um Process Technologies & Beyond
  • Configured for 200mm/300mm wafers
  • Single Open Cassette Loader
  • Defect Sensitivity:
    1. Normal Illumination- 0.079 Defect Sensitivity
    2. Oblique Illumination- 0.060 Defect Sensitivity
    3. 005 ppm Haze Sensitivity
  • Real Time Defect Classification (RTDC)
  • Defect Map & Histogram with Zoom Micro View Measurement Capability
  • Illumination: 30 mW Argon-Ion Laser, 488nm Wavelength
Sample Requirements
  • Substrate: 6” and 8” wafers
  • Unpatterned wafers
  • Substrate thickness: adjustable up to 12 mm
  • Requires very flat sample
  • Sample material should scatter less than 90% of incident light
How Surfscan Works

In a Surfscan® system, deep ultraviolet (DUV) through red light (depending on the system and options) laser beam is focused on the wafer surface and the reflected and scattered light is measured by a series of detectors. The signature (intensity as a function of angle) of the scattered light can be modelled to determine and equivalent scattering center size.

The beam is scanned to generate an image, and the system simultaneously detects and records several types of defect: haze, scratches, and – relevantly to particle analysis – light particle defects.

A Surfscan® instrument is able to (through the appropriate optical model) transform the scattered light signal into quantitative metrics on particle / point-defect size, height, and spatial distribution across the wafer. The system can output numerical data tallying the count and properties of the particles found, as well as 2D and 3D visualizations of all defects it identified.

Comparison link sent successfully
Please use valid email address
You need to have at least 2 techniques to compare
You can select maximum 5 techniques
Covalent uses cookies to improve your browsing experience and to help you access the most relevant information and services efficiently. To learn more, view our
I Accept Cookies
techniques selected
Select at least 2 techniques to compare Compare techniques