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TEM Sample Preparation Facilities

Non-mechanical Sample Preparation

Ion milling involves a sputtering process that is capable of removing very fine quantities of sample material. This method is often used as a final polish for TEM specimens that have been previously polished by mechanical means. Ion milling utilizes an inert gas such as Argon which passes through an electric field to generate a stream of plasma that is directed at the region of interest on the sample. Acceleration energies are generally from a few hundred volts to a few kilovolts. The TEM sample may be rotated to promote even polishing as well as tilted to control the angle of milling. The sputtering rate of ion milling is limited to a few tens of microns per hour, limiting the method to already pre-thinned samples requiring only final milling.

FEI HELIOS 600 Dual Beam FIB

More recently, methods involving the use of focused ion beam tools (FIB) have been used to prepare samples for TEM examination from larger bulk materials. A principal advantage of the FIB technique is that the nanometer-scale resolution allows for a precise region of interest to be chosen for thinning. The drawback of FIB milling is that it causes surface damage in the form of amorphization as well as Ga implantation. The damaged layer can be minimized by FIB milling with lower acceleration voltages, or by subsequent milling with a low-voltage Argon ion beam.

Fischione Model 1040 Nanomill TEM Preparation Tool

  • Ultra-low voltage ion source
  • Concentrated Argon ion beam
  • Removes amorphous and Ga implanted layers
  • Post-FIB processing and milling of mechanically thinned samples
  • Liquid Nitrogen cooled stage
  • Oil free vacuum system

Gatan PIPS (Precision Ion Polishing System)

  • High milling rates at angles from less than 1 degree to 10 degrees.
  • Ion beams are can be modulated for both single or double sector milling
  • Extremely rapid venting for quick sample exchange
  • CCD imagery for real time video monitoring
  • Oil free vacuum system
  • Liquid Nitrogen cooled stage

Fischione Model 1010 dual mill

  • Precision ion milling system for TEM specimens.
  • O-45 degrees of milling angle
  • Variable energy milling
  • Fully programmable  milling parameters
  • Adjustable rocking angle
  • LN2 specimen cooling to eliminate artifacts
  • Oil free vacuum system

Gatan Model 681 High Resolution Ion beam coater

  • Ion beam based sputter coating system which provides continuous, ultra thin, amorphous coatings that are ideal for electron microcopy.
  • More uniform coating than that produced by traditional evaporation, magnetron or RF sputtering.
  • Ultra fast specimen exchange.
  • Able to deposit Carbon or Chromium
  • Liquid Nitrogen anti contamination trap

Mechanical Sample Preparation

Mechanical polishing is one methodology often used for preparing TEM samples. Polishing needs to be performed to a high degree of accuracy and quality to ensure uniformity of thickness, smooth, and defect free region of interest. Dimpling and tripod polishing are generally utilized in conjunction with hard abrasives (films and slurries) composed of such materials as diamond, aluminum oxide, and cubic boron nitride. Even after polishing, additional thinning methods such as ion milling may be required in some cases.

Allied Multiprep Polisher

  • Enables precise semiautomatic sample preparation of a wide range of materials.
  • Enables fully controllable parallel polishing, precise angle polishing, and site specific polishing.
  • Provides for reproducible samples by eliminating inconsistencies between users.
  • Eliminates the need for handheld jigs.
  • Enables quantifiable removal of sample material and controllable rate of polish