Bright color coatings for electronic devices
An electronic device may include conductive structures such as conductive housing structures. A high-brightness, visible-light-reflecting coating may be formed on the conductive structures. The coating may have adhesion and transition layers and an uppermost coloring layer on the adhesion and transition layers. At least the uppermost coloring layer may be deposited using a high impulse magnetron sputtering (HiPIMS) process. The uppermost coloring layer may include a TiCrN film, a TiCrCN film, a TiCN film, or a metal nitride film that contains Ti, Zr, Hf, or Cr. The coating may exhibit a high-brightness gold color.
1 . A cellular telephone comprising:
a conductive substrate comprising a conductive housing wall; and
a coating on the conductive housing wall and having a color, the coating comprising:
adhesion and transition layers, and
an uppermost layer on the adhesion and transition layers, wherein the uppermost layer comprises a TiCrCN film and wherein an atomic percentage of Cr atoms in the TiCrCN film is greater than or equal to 12%.
2 . The cellular telephone of claim 1 , wherein the coating has an L* value greater than 70 in a CIELAB color space, an a* value between 0 and 5 in the CIELAB color space, and a b* value between 10 and 20 in the CIELAB color space.
3 . The cellular telephone of claim 2 , wherein the atomic percentage of Cr atoms in the TiCrCN film is less than 20%.
4 . The cellular telephone of claim 3 , wherein an atomic percentage of Ti atoms in the TiCrCN film is less than 60%.
5 . The cellular telephone of claim 4 , wherein the TiCrCN film is deposited on the adhesion and transition layers using a high impulse magnetron sputtering (HiPIMS) process.
6 . Apparatus comprising:
a substrate; and
a coating on the substrate, the coating comprising:
adhesion and transition layers, wherein the adhesion and transition layers comprise a Cr seed layer on the substrate and a CrSiN transition layer on the Cr seed layer, and
an uppermost layer on the adhesion and transition layers, the uppermost layer comprising a TiCrCN film, wherein the TiCrCN film is on the CrSiN transition layer, and wherein the coating has an L* value greater than 70 in a CIELAB color space, an a* value between 0 and 5 in the CIELAB color space, and a b* value between 10 and 15 in the CIELAB color space.
7 . The apparatus of claim 6 , wherein the TiCrCN film is opaque.
8 . The apparatus of claim 6 , wherein the TiCrCN film has a thickness between 0.1 and 1.0 microns.
9 . The apparatus of claim 8 , wherein an atomic percentage of Cr atoms in the TiCrCN film is greater than 5% and less than 20%.
10 . The apparatus of claim 9 , wherein an atomic percentage of N atoms in the TiCrCN film is between 25% and 42%.
11 . The apparatus of claim 6 , wherein an atomic percentage of Cr atoms in the TiCrCN film is greater than 5% and less than 20%.
12 . The apparatus of claim 11 , wherein an atomic percentage of N atoms in the TiCrCN film is greater than 25% and less than 40%.
13 . The apparatus of claim 12 , wherein an atomic percentage of C atoms in the TiCrCN film is greater than 1% and less than 15%.
14 . The apparatus of claim 6 , wherein the apparatus comprises a wristwatch and the substrate comprises a conductive housing wall of the wristwatch.
15 . The apparatus of claim 6 , wherein the TiCrCN film is deposited on the adhesion and transition layers using a high impulse magnetron sputtering (HiPIMS) process.
16 . The apparatus of claim 15 , wherein the adhesion and transition layers are deposited on the substrate using a non-HiPIMS magnetron sputtering process.
17 . An electronic device, comprising:
a structure; and
a coating on the structure, the coating comprising:
adhesion and transition layers, wherein the adhesion and transition layers comprise a Cr layer on the structure and a CrSiN layer on the Cr layer, and
a TiCrCN layer on the adhesion and transition layers, wherein the TiCrCN layer is an outermost layer of the coating.
18 . The electronic device of claim 17 , wherein the coating has an L* value greater than 70 in a CIELAB color space, an a* value between 0 and 5 in the CIELAB color space, and a b* value between 10 and 15 in the CIELAB color space, and the structure comprises a conductive housing wall.