NanoSpec Spectrophotometer


Facts

  • The SMFL has two Nanometrics Spectrophotometers
    • Nanometrics Model 210 is in Wet Etch 1.
    • Nanometrics Model 200 is in Wet Etch 2
  • The basic operating principle of a spectrophotometer is that the intensity of monochromatic reflected light depends strongly on film thickness because of interference.
    • The film thicknesses are comparable to the wavelength of the incident light.
  • The machine uses a computer-controlled grating monochromator and a photomultiplier tube detector to measure the reflected optical spectrum over the 350 to 800 nm wavelength band) from a bare silicon reference wafer and from the wafer under test.
  • Given an index of refraction for a thin film and the two measured spectrums, the computer will analyze the interference pattern to determine film thickness.

Personnel


Tool & Process Information

  • The Nanospec may be used to manually measure film thickness on wafers, wafer pieces or individual devices.  Magnification ranges from 5x to 100x.
  • If you do not see the octogon, make sure the aperture is closed.
  • The filter should always be in, unless the tool tells you to take it out. (Nitride on Oxide)
  • When measuring Thin Oxide or Thin Nitride, it is very important to carefully focus on the reference wafer as well as the sample, because the system is only measuring the intensity of a single wavelength.

ProgramIndexRangeFilter
1Oxide on Si1.45400-30,000ÅIn
2Nitride on Si2.00400-10,000ÅIn
3Negative Resist on Si1.55500-40,000ÅIn
4Polysilicon on Oxide3.0400-10,000ÅIn
5Negative Resist on Si1.554,000-30,000ÅIn
6Nitride on Oxide2.00300-3,500ÅOut
7Thin Oxide on Si1.45100-500ÅIn
8Thin Nitride on Si2.00100-500ÅIn
9Polyimide on Si1.78500-10,000ÅIn
10Positive Resist on Si1.64500-40,000ÅIn
11Positive Resist on Oxide1.644,000-30,000Å


Manuals & Users