Please select your country or region to be
directed to the appropriate Lesker site.

Molybdenum Oxide MoO3 Evaporation Process Notes

Molybdenum oxide is a chemical compound with a chemical formula of MoO3. It is white to pale yellow in color with a melting point of 795°C, a density of 4.69 g/cc, and a vapor pressure of 10-4 Torr at ~900°C. It is primarily used to manufacture pure molybdenum metal. It is evaporated under vacuum to make transparent electrodes for photovoltaic cells.

Molybdenum Oxide MoO3 Specifications

Material TypeMolybdenum Oxide
Color/AppearanceWhite to Pale Yellow, Crystalline Solid
Melting Point (°C)795
Theoretical Density (g/cc)4.69
Type of BondIndium, Elastomer
Z Ratio**1.00
Thermal Evaporation Techniques Boat:  Mo
Basket:  Mo
Crucible:  Al2O3, BN
Temp. (°C) for Given Vap. Press. (Torr) 10-4:  ~900
CommentsSlight oxygen loss.

** The z-ratio is unknown. Therefore, we recommend using 1.00 or an experimentally determined value. Please click here for instructions on how to determine this value.


Empirical Determination of Z-Factor

Unfortunately, Z Factor and Shear Modulus are not readily available for many materials. In this case, the Z-Factor can also be determined empirically using the following method:

  • Deposit material until Crystal Life is near 50%, or near the end of life, whichever is sooner.
  • Place a new substrate adjacent to the used quartz sensor.
  • Set QCM Density to the calibrated value; Tooling to 100%
  • Zero thickness
  • Deposit approximately 1000 to 5000 A of material on the substrate.
  • Use a profilometer or interferometer to measure the actual substrate film thickness.
  • Adjust the Z Factor of the instrument until the correct thickness reading is shown.

Another alternative is to change crystals frequently and ignore the error. The graph below shows the % Error in Rate/Thickness from using the wrong Z Factor. For a crystal with 90% life, the error is negligible for even large errors in the programmed versus actual Z Factor.

Molybdenum Oxide (MoO3) Products
Deposition Materials FAQ
Click here for answers to some of the most common questions we are asked.
Contact Us
Contact Us
To contact someone directly, please click here, or call +1 412 387 9200 to get in contact with your dedicated sales team.
Contact Us - Molybdenum Oxide MoO3 Evaporation Process Notes