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Atomic layer deposition for fabrication of HfO2/Al2O3 thin films with high laser-induced damage thresholds.

Wei Y, Pan F, Zhang Q, Ma P - Nanoscale Res Lett (2015)

Bottom Line: Reasons for film damaged were also investigated.The LIDT of the HfO2/Al2O3 anti-reflector film reached 18 J/cm(2), the highest value reported for ALD single and anti-reflect films.In addition, it was shown that the LIDT could be improved by further altering the process parameters.

View Article: PubMed Central - PubMed

Affiliation: Chengdu Fine Optical Engineering Research Center, Chengdu, Sichuan 610041 P. R. China.

ABSTRACT
Previous research on the laser damage resistance of thin films deposited by atomic layer deposition (ALD) is rare. In this work, the ALD process for thin film generation was investigated using different process parameters such as various precursor types and pulse duration. The laser-induced damage threshold (LIDT) was measured as a key property for thin films used as laser system components. Reasons for film damaged were also investigated. The LIDTs for thin films deposited by improved process parameters reached a higher level than previously measured. Specifically, the LIDT of the Al2O3 thin film reached 40 J/cm(2). The LIDT of the HfO2/Al2O3 anti-reflector film reached 18 J/cm(2), the highest value reported for ALD single and anti-reflect films. In addition, it was shown that the LIDT could be improved by further altering the process parameters. All results show that ALD is an effective film deposition technique for fabrication of thin film components for high-power laser systems.

No MeSH data available.


Related in: MedlinePlus

Experimental setup and laser beam profile. (a) Laser damage testing bench; (b) Typical beam profile at sample position.
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Fig1: Experimental setup and laser beam profile. (a) Laser damage testing bench; (b) Typical beam profile at sample position.

Mentions: Optical properties such as the absorption, refractive index, and transmission spectra were analyzed in detail. For thin films designed for laser applications, the most important property is the LIDT. Therefore, the LIDTs were measured for comparison using a Nd:YAG laser in 1.000 on 1 mode (ISO 21254) [10], at a wavelength of 1,064 nm, a pulse duration of 3 ns (FWHM), and a pulse frequency of 100 Hz. The experimental setup and laser beam profile are shown in Figure 1. The laser was focused to provide a far-field circular Gaussian beam with a diameter of 300 μm at 1/e2 of the maximum intensity. The angle of incidence was close to 0°. A Si-photodiode was used to monitor the scattered light variation and served as an online detection system. The damaged sites were reconfirmed offline using a Nomarski microscope with magnification ≤ ×200.Figure 1


Atomic layer deposition for fabrication of HfO2/Al2O3 thin films with high laser-induced damage thresholds.

Wei Y, Pan F, Zhang Q, Ma P - Nanoscale Res Lett (2015)

Experimental setup and laser beam profile. (a) Laser damage testing bench; (b) Typical beam profile at sample position.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4385131&req=5

Fig1: Experimental setup and laser beam profile. (a) Laser damage testing bench; (b) Typical beam profile at sample position.
Mentions: Optical properties such as the absorption, refractive index, and transmission spectra were analyzed in detail. For thin films designed for laser applications, the most important property is the LIDT. Therefore, the LIDTs were measured for comparison using a Nd:YAG laser in 1.000 on 1 mode (ISO 21254) [10], at a wavelength of 1,064 nm, a pulse duration of 3 ns (FWHM), and a pulse frequency of 100 Hz. The experimental setup and laser beam profile are shown in Figure 1. The laser was focused to provide a far-field circular Gaussian beam with a diameter of 300 μm at 1/e2 of the maximum intensity. The angle of incidence was close to 0°. A Si-photodiode was used to monitor the scattered light variation and served as an online detection system. The damaged sites were reconfirmed offline using a Nomarski microscope with magnification ≤ ×200.Figure 1

Bottom Line: Reasons for film damaged were also investigated.The LIDT of the HfO2/Al2O3 anti-reflector film reached 18 J/cm(2), the highest value reported for ALD single and anti-reflect films.In addition, it was shown that the LIDT could be improved by further altering the process parameters.

View Article: PubMed Central - PubMed

Affiliation: Chengdu Fine Optical Engineering Research Center, Chengdu, Sichuan 610041 P. R. China.

ABSTRACT
Previous research on the laser damage resistance of thin films deposited by atomic layer deposition (ALD) is rare. In this work, the ALD process for thin film generation was investigated using different process parameters such as various precursor types and pulse duration. The laser-induced damage threshold (LIDT) was measured as a key property for thin films used as laser system components. Reasons for film damaged were also investigated. The LIDTs for thin films deposited by improved process parameters reached a higher level than previously measured. Specifically, the LIDT of the Al2O3 thin film reached 40 J/cm(2). The LIDT of the HfO2/Al2O3 anti-reflector film reached 18 J/cm(2), the highest value reported for ALD single and anti-reflect films. In addition, it was shown that the LIDT could be improved by further altering the process parameters. All results show that ALD is an effective film deposition technique for fabrication of thin film components for high-power laser systems.

No MeSH data available.


Related in: MedlinePlus