SRS QCM-200 Crystals for Liquid Monitoring


Sold in packs of 4 (four) crystals


These 1” diameter AT cut polished ​quartz crystal sensors are compatible with Maxtek PM 700 series, RQCM monitors, PLO-10i,
and Stanford Research Systems (SRS) QCM100 QCM200 and EQCM quartz crystal microbalance systems.


Essentially, these are AT-cut crystals very much like standard vacuum monitor crystals, with four exceptions:

  1. the diameter is larger, allowing for a very clean resonance spectrum and resulting measurement stability.
  2. the crystals are flat, unlike the planoconvex design of a vacuum monitor blank.
  3. the crystals are often polished on both sides, to minimize the “dragging” of water by the crystal surface during oscillation and 4) the electrode pattern is a wrap around design, which means that the crystal can be completely contacted electrically from one side. This latter feature is a necessity since the crystal sensor head must be submerged in water. An O-ring seal is incorporated in liquid monitor sensor heads to prevent electrical shorting.

Our Packaging

The crystals are shipped in a clean room compatible package of 4 crystals. Careful attention to the design ensures that the center of the crystal, where the actual measurement occurs (within a radius of 3 mm from the center), is not touched or contaminated by the plastic. We use pharmaceutical grade PETG plastic for the top, and hand cleaned polystyrene for the base. This difference in plastics is needed due to the buildup of static charge between two pieces of PETG. Some manufacturers use anti-static PETG, but this contains a polymer agent that will eventually leach onto the crystal surface. In other words, our packages were designed from the ground up with the same exacting standards as the crystals themselves.

Possible Applications

  • DNA and RNA hybridization research
  • Immunosensors
  • Bubble formation
  • Redox and conductive polymer research
  • Double-layer characterization
  • Corrosion studies
  • Surface oxidation
  • Metal plating applications like CIGS, PVD, CVD
  • Gas-phase mass detection
  • Electro-chemistry
  • Sorption sensors
  • Moisture analyzers
  • Particulate monitors
  • Antigen-antibody reactions
  • Protein adsorption
  • Detection of virus capsids, bacteria, mammalian cells
  • Biofouling and antifouling
  • Biomembranes and biomaterials
  • Protein-protein interactions
  • Self-assembled monolayers— SAMs
  • Molecularly imprinted polymers— MIPs
  • Langmuir/Langmuir-Blodgett films
  • Laser ablation, desorption and breakdown studies
  • MEMS nanomaterials
  • Contamination monitors
  • Electrovalency measurements
  • Hydrogen absorption on metal films


Additional information

Weight .05 lbs
Dimensions 3.75 × 3.75 × .35 in
Package Quantity

4 crystals per pack

Harmonized Code


Related Products