Fluorinated amorphous carbon films were deposited using microwave electron cyclotron resonance chemical vapor deposition (ECR-CVD) reactor with CF4 and C8H6 as source gas and were annealed in nitrogen ambience for the...Fluorinated amorphous carbon films were deposited using microwave electron cyclotron resonance chemical vapor deposition (ECR-CVD) reactor with CF4 and C8H6 as source gas and were annealed in nitrogen ambience for the investigating of their thermal stability .The relative concentration of C=C bond and optical bandgap were obtained by Fourier Transform Infrared (FTIR) spectroscopy and Ultraviolet-Visible (UV-VIS ) spectrum, respectively. It has been demonstrated that there is a close relationship between relative concentration of C=C bond and optical bandgap, and the films deposited at a higher microwave power have a lower optical bandgap and a better thermal stability.展开更多
One of the important characteristic of adaptive mirrors is the thermal stability of surface flatness. In this paper, the thermal stability from 13℃ to 25℃ of a 20-actuator bimorph deformable mirror is tested by a Sh...One of the important characteristic of adaptive mirrors is the thermal stability of surface flatness. In this paper, the thermal stability from 13℃ to 25℃ of a 20-actuator bimorph deformable mirror is tested by a Shack-Hartmann wavefront sensor. Experimental results show that, the surface P-V of bimorph increases nearly linearly with ambient temperature. The ratio is 0.11 μm/℃ and the major component of surface displacement is defocused, compared with which, astigmatism, coma and spherical aberration contribute very small. Besides, a finite element model is built up to analyse the influence of thickness, thermal expansion coefficient and Young＇s modulus of materials on thermal stability. Calculated results show that bimorph has the best thermal stability when the materials have the same thermal expansion coefficient. And when the thickness ratio of glass to PZT is 3 and Young＇s modulus ratio is approximately 0.4, the surface instability behaviour of the bimorph manifests itself most severely.展开更多
Ge-Ga-S thin films were deposited by magnetron sputtering with mean coordination number(MCN)ranging from 2.46 to 2.94.The physical properties of the Ge-Ga-S films,including optical band gap,refractive index,and thickn...Ge-Ga-S thin films were deposited by magnetron sputtering with mean coordination number(MCN)ranging from 2.46 to 2.94.The physical properties of the Ge-Ga-S films,including optical band gap,refractive index,and thickness,vary with the time of heat treatment.Based on the analysis of the topology model,it is concluded that the Ge-Ga-S thin films with components close to the stoichiometric ratio can form the most Ga-S bonds and Ga-S bonds,and the physical properties of the Ge27.3Ga6.3S66.3(MCN=2.62)film are the most stable.This is an important reference for thin film photonic devices.展开更多
文摘Fluorinated amorphous carbon films were deposited using microwave electron cyclotron resonance chemical vapor deposition (ECR-CVD) reactor with CF4 and C8H6 as source gas and were annealed in nitrogen ambience for the investigating of their thermal stability .The relative concentration of C=C bond and optical bandgap were obtained by Fourier Transform Infrared (FTIR) spectroscopy and Ultraviolet-Visible (UV-VIS ) spectrum, respectively. It has been demonstrated that there is a close relationship between relative concentration of C=C bond and optical bandgap, and the films deposited at a higher microwave power have a lower optical bandgap and a better thermal stability.
基金supported by the Key Project of National Natural Science Foundation of China (Grant No 60438030)
文摘One of the important characteristic of adaptive mirrors is the thermal stability of surface flatness. In this paper, the thermal stability from 13℃ to 25℃ of a 20-actuator bimorph deformable mirror is tested by a Shack-Hartmann wavefront sensor. Experimental results show that, the surface P-V of bimorph increases nearly linearly with ambient temperature. The ratio is 0.11 μm/℃ and the major component of surface displacement is defocused, compared with which, astigmatism, coma and spherical aberration contribute very small. Besides, a finite element model is built up to analyse the influence of thickness, thermal expansion coefficient and Young＇s modulus of materials on thermal stability. Calculated results show that bimorph has the best thermal stability when the materials have the same thermal expansion coefficient. And when the thickness ratio of glass to PZT is 3 and Young＇s modulus ratio is approximately 0.4, the surface instability behaviour of the bimorph manifests itself most severely.
基金the National Natural Science Foundation of China(Grant Nos.61675105,61775111,and 61904091)Ningbo Optoelectronic Materials and Devices Laboratory(Grant No.2009B21007)。
文摘Ge-Ga-S thin films were deposited by magnetron sputtering with mean coordination number(MCN)ranging from 2.46 to 2.94.The physical properties of the Ge-Ga-S films,including optical band gap,refractive index,and thickness,vary with the time of heat treatment.Based on the analysis of the topology model,it is concluded that the Ge-Ga-S thin films with components close to the stoichiometric ratio can form the most Ga-S bonds and Ga-S bonds,and the physical properties of the Ge27.3Ga6.3S66.3(MCN=2.62)film are the most stable.This is an important reference for thin film photonic devices.
