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Thin-film transparent heaters (TFTHs) are gaining popularity in optoelectronics and a variety of domestic applications, including smart windows, car defrosters, and other devices. The deposition and characterization of TFTHs made of gallium-doped zinc oxide (GZO) are presented in this work. GZO thin films were deposited via pulsed laser deposition on glass substrates with varying oxygen partial pressures from 0 to 10 mTorr during deposition. The samples demonstrated very low sheet resistance values between 5 and 17 Ω/sq from 0 to 10 mTorr, respectively. UV/vis transmission spectra revealed that TFTHs have a high optical transparency above 80%. GZO-based TFTHs demonstrated a consistent and repeatable joule heating effect, with temperatures reaching 76 °C with a low input voltage of 10 V. This research could guide the future use of GZO as a transparent conducting oxide material for many potential cost-effective applications from low-powered electronics to lightweight and wearable devices.
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Effect of microstructure on the optical properties of sputtered iridium thin films
The refractory metal iridium has many applications in high performance optical devices due to its high reflectivity into X-ray frequencies, low oxidation rate, and high melting point. Depositing Ir via magnetron sputtering produces high quality thin films, but the chamber pressure and sputter conditions can change Ir film microstructure on the nanoscale. Film microstructure is commonly examined through microscopy of film cross-sections, which is both a destructive characterization method and time consuming. In this work, we have utilized a non-destructive characterization technique, spectroscopic ellipsometry, to correlate the optical properties of the metal films with their structural morphologies, enabling large-scale inspection of optical components or the ability to customize the metal refractive index for the application at hand. The optical properties of Ir thin films deposited at chamber pressures from 10 mTorr to 25 mTorr are reported and compared to microscopy and resistivity results. The measurements were conducted with films deposited both on a bare wafer and on a titanium sublayer.
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- Award ID(s):
- 1806311
- PAR ID:
- 10142574
- Publisher / Repository:
- Optical Society of America
- Date Published:
- Journal Name:
- Optical Materials Express
- Volume:
- 10
- Issue:
- 4
- ISSN:
- 2159-3930
- Format(s):
- Medium: X Size: Article No. 1120
- Size(s):
- Article No. 1120
- Sponsoring Org:
- National Science Foundation
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