Difference between revisions of "Filmetrics F40-UV Microscope-Mounted"

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|super = Ning Cao
 
|super = Ning Cao
 
|picture=Filmetrics F40-UV - system pic 01.jpg
 
|picture=Filmetrics F40-UV - system pic 01.jpg
|type = Inspection,_Test_and_Characterization
+
|type = Inspection, Test and Characterization
 
|location = Bay #4
 
|location = Bay #4
|description = Measures thin-film thickness/index in small regions via optical reflectometry through a microscope.
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|description = Microscope-mounted optical reflectometry
 
|manufacturer = Filmetrics Inc.
 
|manufacturer = Filmetrics Inc.
 
|model = F40-UV
 
|model = F40-UV
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* [[Filmetrics F40-UV Quick Start|Quick Start Procedure]]
 
* [[Filmetrics F40-UV Quick Start|Quick Start Procedure]]
   
== Screenshots + Examples ==
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== Examples ==
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[[File:Filmetrics_F40-UV_-_Measurement_screenshot_on_metal_pad_01.PNG|alt=example spectrum curve fit|none|thumb|500x500px|Screenshot showing 10x microscope view and optical spectrum/curve fitting of the SiO2 film thickness on top of Platinum contact metal.]]
 
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=== Good Curve-Fitting ===
 
Do not believe your thickness measurements unless the red/blue curves show a reasonably good match![[File:Filmetrics_F40-UV_-_Measurement_screenshot_on_metal_pad_01.PNG|alt=example spectrum curve fit|none|thumb|500x500px|Screenshot showing 10x microscope view and optical spectrum/curve fitting of the SiO2 film thickness on top of Platinum contact metal.]]
   
 
[[File:Filmetrics F40-UV - spectrum curve fit 07.jpg|alt=example spectrum curve fit|none|thumb|300x300px|A good fit should show the Calculated (red) curve overlay on top of the Measureed (blue) curve.]]
 
[[File:Filmetrics F40-UV - spectrum curve fit 07.jpg|alt=example spectrum curve fit|none|thumb|300x300px|A good fit should show the Calculated (red) curve overlay on top of the Measureed (blue) curve.]]
  +
 
=== Checking whether a dry etch is complete ===
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The F40-UV is very useful for measuring whether a thin-film has been completely removed during a dry etch. This is similar to using [[Laser Etch Monitoring|laser monitoring]] during the etch, except that the microscope enables you to measure inside small patterned areas that a laser monitor spot may not fit inside.
  +
  +
In the following example, we are trying to etch away the SiO<sub>2</sub> from on top of a Platinum contact metal. The 20x objective allows us to measure the SiO2 thickness on top of the Platinum as we continue to etch in 1 minute increments, measuring in between etches.
  +
  +
Finally, when the SiO2 has been fully removed, we see that we can't get a good fit between the measured (blue) and simulated (red) data.
  +
  +
Since the Platinum layer is thick enough to be opaque to visible light (>50nm), we just modelled this as SiO2 on top of Platinum, ignoring any other materials below the platinum.
 
{| class="wikitable"
 
{| class="wikitable"
  +
|+
|+Using the F40-UV to check whether a dry etch is complete.
 
![[File:Filmetrics F40-UV - SiO Etch 4m+4m - Incomplete Etch.png|alt=Example Screenshot of incomplete SiO2 etch|none|thumb|400x400px|Incomplete Dry-Etch, showing some residual SiO2 left.]]
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![[File:Filmetrics F40-UV - SiO Etch 4m+4m - Incomplete Etch.png|alt=Example Screenshot of incomplete SiO2 etch|none|thumb|400x400px|Incomplete Dry-Etch, showing some residual SiO2 left. "Goodness of Fit" is close to 1.0 in the results pane, and the red+blue curves match closely so we believe the measurement.]]
![[File:Filmetrics F40-UV - 2018-11-08 - SiO Etch 4m+4m+1m - Fully Removed.png|alt=Example screenshot of fully removed SiO2 etch|none|thumb|400x400px|After re-etching, measurement shows bad fit (red and blue curves), indicating the SiO2 film has been fully removed.]]
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![[File:Filmetrics F40-UV - 2018-11-08 - SiO Etch 4m+4m+1m - Fully Removed.png|alt=Example screenshot of fully removed SiO2 etch|none|thumb|400x400px|After re-etching, measurement shows bad fit (red and blue curves), and "Goodness of Fit" = 0 in the results pane.
  +
The thickness value shown is not real, and this indicates that the SiO2 film has been fully removed since no parameter can give a good fit.
  +
]]
 
|}
 
|}

Revision as of 11:23, 31 May 2019

Filmetrics F40-UV Microscope-Mounted
Filmetrics F40-UV - system pic 01.jpg
Tool Type Inspection, Test and Characterization
Location Bay #4
Supervisor Ning Cao
Supervisor Phone (805) 893-4689
Supervisor E-Mail ningcao@ece.ucsb.edu
Description Microscope-mounted optical reflectometry
Manufacturer Filmetrics Inc.
Model F40-UV



About

The Filmetrics F40-UV is a microscope-mounted thin-film measurement system, allowing you to non-destructively measure thin-film thicknesses in small (patterned) areas on your sample. It is an optical reflectometer, acquiring reflection spectra between 400-900nm optical wavelengths (Vis to Near-IR) with a regular halogen microscope light source. The Filmetrics software then performs curve-fitting to determine the thickness and/or refractive index of the measured films.

Capabilities

  • Measure optically transparent thin-films down to ~30nm thickness.
  • Microscope Objectives: 10x, 20x, 50x, 100x, 150x
  • Acquire Optical Reflection Spectra from 400-900nm
  • Spectrometer/Detector is capable of detecting down to UV ~190nm, but light source does not support this wavelength.
  • Reflectivity curve-fitting for thin-film thickness analysis, supporting many common materials (Si3N4, SiO2 dielectrics, Si, GaAs, InP semiconductors, metals, photoresists etc.)

Operating Procedures

Examples

Good Curve-Fitting

Do not believe your thickness measurements unless the red/blue curves show a reasonably good match!

example spectrum curve fit
Screenshot showing 10x microscope view and optical spectrum/curve fitting of the SiO2 film thickness on top of Platinum contact metal.
example spectrum curve fit
A good fit should show the Calculated (red) curve overlay on top of the Measureed (blue) curve.

Checking whether a dry etch is complete

The F40-UV is very useful for measuring whether a thin-film has been completely removed during a dry etch. This is similar to using laser monitoring during the etch, except that the microscope enables you to measure inside small patterned areas that a laser monitor spot may not fit inside.

In the following example, we are trying to etch away the SiO2 from on top of a Platinum contact metal. The 20x objective allows us to measure the SiO2 thickness on top of the Platinum as we continue to etch in 1 minute increments, measuring in between etches.

Finally, when the SiO2 has been fully removed, we see that we can't get a good fit between the measured (blue) and simulated (red) data.

Since the Platinum layer is thick enough to be opaque to visible light (>50nm), we just modelled this as SiO2 on top of Platinum, ignoring any other materials below the platinum.

Example Screenshot of incomplete SiO2 etch
Incomplete Dry-Etch, showing some residual SiO2 left. "Goodness of Fit" is close to 1.0 in the results pane, and the red+blue curves match closely so we believe the measurement.
Example screenshot of fully removed SiO2 etch
After re-etching, measurement shows bad fit (red and blue curves), and "Goodness of Fit" = 0 in the results pane. The thickness value shown is not real, and this indicates that the SiO2 film has been fully removed since no parameter can give a good fit.