Apparatus and Method for In-Situ Thickness and Stoichiometry Measurement of Thin Films - Reference #101

Background

Thin films are used in the production of electronic and optoelectronic devices, such as computer hard drives and quantum well laser diodes. Measurement of the thickness and stoichiometry of thin films during manufacturing of these and other products is ideal for monitoring the quality of the production process. However, present measurement methods, such as Reflection High Energy Electron Diffraction (RHEED) and ellipsometry, are either limited in their ability to provide real-time feedback during manufacturing or are overly complex.

 

Technology Description

Unlike conventional technologies, this invention utilizes the Alpha Particle Energy Loss Method (AEL) to provide real-time, in-situ thickness and stoichiometry measurements of thin films, particularly those made by Molecular Beam Epitaxy (MBE). The method can also be applied to thin films made by other processes such as chemical vapor deposition, sputtering, plasma coating, etc.

The method of measuring thickness and stoichiometry comprises implanting alpha-emitting nuclei in a substrate, and then measuring the energy lost by the alpha particles as they traverse a thin film grown later on that substrate. An alpha particle detector operates within the growth chamber environment to enable real-time measurements.

 

Advantages

  • Precise and simultaneous determinations of absolute thickness and stoichiometry
  • AEL method allows direct measurement of the thin film growth rate, and thus enables determination of the sticking coefficient in a single growth run
  • Provides real-time measurements during manufacturing process
  • Easier to implement than ellipsometry, which is dependent on optical reflectivity and thin film interference effects
  • Method is cheaper and simpler to implement than Rutherford Back Scattering
  • Simple and practical method to address actual needs in specific technological applications

 

Applications

  • Manufacturing of microchips, semiconductors, electronic devices
  • In situ monitoring of damage (degradation, abrasion, erosion) to optical coatings
  • Analysis of degradation on metallic surfaces (e.g. on airplane turbines)

 

Commercial Status

Patent protection has been obtained in the U.S., Europe and Australia and is still pending in a few other jurisdictions worldwide. A prototype has been constructed and successfully tested. This technology is available for immediate licensing or collaborative development. Please contact us for further information.

 

Contact

Phil Gardner
Head, Technology Transfer Division
Phone: 604.222.7436
Email: ttadmin@triumf.ca
* Please quote reference number 101.