- Which method should I use to deposit the enhancing metal film?
- Which cell base material should I choose?
- What is the difference between the J1 and the J1W?
Which method should I use to deposit the enhancing metal film?
Which method should I use to deposit the enhancing metal film?
We have written an overview of the various methods available for depositing metal films on ATR crystals, which can provide some context for the following remarks. Metal films sputtered directly on most crystal materials have extremely poor adhesion due to lattice mismatch of the metal and the crystal material. It is possible to use an electroless chemical deposition method, however this method also suffers from the same adhesion problems as directly sputtered films. It is also limited to Si crystals since the process involves a galvanic reaction with the Si surface. Our recommended method is to first sputter a layer of conductive metal oxide on top of the crystal, and then electrochemically deposit the metal film from an electrolyte containing the desired metal salt.
Which cell base material should I choose?
We generally recommend PEEK for improved life and superior mechanical robustness, however PTFE is available should you need the additional chemical resistance. More details can be found on our product page.
What is the difference between the J1 and the J1W?
The J1W uses IRUBIS micromachined silicon wafers, while the J1 uses a face-angled crystal. The main advantage of the IRUBIS wafers (J1W) is the reduced optical path length, which minimizes the attenuation due to Si phonon modes. The wafers are low cost and can be reused, however they are also fragile, and they are easy to break unless extra care is taken when assembling the cell. The face-angled crystal (J1) has the advantage of being easily reusable by polishing, and it comes in a variety of materials and face angles, as well as with anti-reflective coatings. The J1 offers a larger surface area, which can allow for the use of a larger aperture for better throughput. If you’re not sure which crystal type you would like to use or you want to use both, we also offer a combination cell which includes a single set of glassware, but with both bases to allow you to use either crystal option.