The price of Iridium has increased significantly in recent years. The price increase has made it difficult to keep the hourly instrument usage cost the same when using an Iridium target. As a result, a decision was made to replace the Iridium target with a Platinum target.
Platinum is a good alternative to Iridium for a number of reasons:
- The density of Platinum (21.45 g/cm3)is very close to the density of Iridium(22.56 g/cm3). This means that roughly the same thickness of coating should work with both materials.
- Platinum has a fine grain size, which is similar to Iridium. This means that the coatings will be uniform and smooth.
- The work function of Platinum (5.65 eV) is very similar to the work function of Iridium(5.63 eV). This means that the sputtering rate will be similar for both materials.
- Platinum can be used in high vacuum coaters, just like Iridium.
Users who are concerned about how this change may affect their sample preparation techniques should check the points above. If a user is inclined to continue to use Iridium they would need to contact the Instrument manager.