Aloha, fun & authoritative answers -- no cost, no registration, no passwords, no popups
(as an eBay Partner & Amazon Affiliate we earn from qualifying purchases)

Home /
T.O.C.
Fun
FAQs
Good
Books
Ref.
Libr.
Adver-
tise
Help
Wanted
Current
Q&A's
Site 🔍
Search
pub  Where the
world gathers for metal finishing
Q&As since 1989



-----

Why Gold coating over Titanium Nitride turns reddish when touched?




2006

We use a PVD (UBM) Machine (with Polycold) to coat Gold over Titanium Nitride. Invariably, we find the color of Gold Coating change to a Reddish Tinge when touched with bare fingers. When wiped with a good cloth, this reddish tinge disappears.

We also find this to happen on the Titanium Nitride Coating, although the TiN coating is visibly very good at a rich greenish yellow color when taken fresh. The color of TiN turns reddish brown in the areas touched.

Can some one help us to identify the actual cause of this?
Sreenivass NV
Premier Systems - Hosur, Tamil Nadu, INDIA



How thick are the films? We tried using TiN for a quartz crystal sensor coating at ~0.15 µm but the surface roughness was ~0.1 um! Unless the gold is thick compared to that roughness it will not "smooth" over the spikes of the TiN surface.
Jeffrey C. Andle
- Westbrook, Maine
2006



I forgot to actually get to the point... The finger oil is absorbed in the rough surface and is optically on the order of the wavelength. The coloration we observed varied depending on roughness and what liquid...
Jeffrey C. Andle
- Westbrook, Maine
2006




(No "dead threads" here! If this page isn't currently on the Hotline your Q, A, or Comment will restore it)

Q, A, or Comment on THIS thread -or- Start a NEW Thread

Disclaimer: It's not possible to fully diagnose a finishing problem or the hazards of an operation via these pages. All information presented is for general reference and does not represent a professional opinion nor the policy of an author's employer. The internet is largely anonymous & unvetted; some names may be fictitious and some recommendations might be harmful.

If you are seeking a product or service related to metal finishing, please check these Directories:

 
Jobshops
Capital
Equipment
Chemicals &
Consumables
Consult'g, Train'g
& Software


About/Contact  -  Privacy Policy  -  ©1995-2024 finishing.com, Pine Beach, New Jersey, USA  -  about "affil links"