Hydrogen-free diamond-like carbon (DLC) thin films were deposited at low temperature (less than 100~C) by an RF magne- tron sputtering facility. DLC films have the ability to change the sound velocity (E/p) in l...Hydrogen-free diamond-like carbon (DLC) thin films were deposited at low temperature (less than 100~C) by an RF magne- tron sputtering facility. DLC films have the ability to change the sound velocity (E/p) in loudspeakers for applications of hard coating. The hydrogen-free DLC films were coated onto PEI diaphragm substrates. The ID/IG ratio and the surface roughness are 2.09 and less than 0.86 nm (Ra) with a scanning area of 50 um x 50 um, respectively. Frequency response analysis of the DLC films on the diaphragm shows that the high frequency response increases by 0.2 dB-5.1 dB (6 kHz-ll.2 kHz), -0.4 dB-1.8 dB (11.8 kHz-20 kHz) on average. On the basis of the results of this study, we validated that it was feasible to sputter hydrogen-free DLC films on polymer substrates for mass production. These results also provided useful parameters for future applications of electro-acoustic devices.展开更多
In order to reduce the noises affixed to the signals when testing high frequency devices,a single-port test mode(S11) is used to test frequency response of high frequency(GHz) and dual-port surface acoustic wave devic...In order to reduce the noises affixed to the signals when testing high frequency devices,a single-port test mode(S11) is used to test frequency response of high frequency(GHz) and dual-port surface acoustic wave devices(SAWDs) in this paper.The feasibility of the test is proved by simulating the Fabry-perot model.The frequency response of the high-frequency dual-port resonant-type diamond SAWD is measured by S11 and the dual-port test mode(S21),respectively.The results show that the quality factor of the device is 51.29 and the 3 dB bandwidth is 27.8 MHz by S11-mode measurement,which is better than the S21 mode,and is consistent with the frequency response curve by simulation.展开更多
文摘Hydrogen-free diamond-like carbon (DLC) thin films were deposited at low temperature (less than 100~C) by an RF magne- tron sputtering facility. DLC films have the ability to change the sound velocity (E/p) in loudspeakers for applications of hard coating. The hydrogen-free DLC films were coated onto PEI diaphragm substrates. The ID/IG ratio and the surface roughness are 2.09 and less than 0.86 nm (Ra) with a scanning area of 50 um x 50 um, respectively. Frequency response analysis of the DLC films on the diaphragm shows that the high frequency response increases by 0.2 dB-5.1 dB (6 kHz-ll.2 kHz), -0.4 dB-1.8 dB (11.8 kHz-20 kHz) on average. On the basis of the results of this study, we validated that it was feasible to sputter hydrogen-free DLC films on polymer substrates for mass production. These results also provided useful parameters for future applications of electro-acoustic devices.
基金supported by the National Natural Science Foundation of China (Nos.50972105 and 60806030)Tianjin Natural Science Foundation (Nos.09JCZDJC16500,08JCYBJC14600 and ZD200709)
文摘In order to reduce the noises affixed to the signals when testing high frequency devices,a single-port test mode(S11) is used to test frequency response of high frequency(GHz) and dual-port surface acoustic wave devices(SAWDs) in this paper.The feasibility of the test is proved by simulating the Fabry-perot model.The frequency response of the high-frequency dual-port resonant-type diamond SAWD is measured by S11 and the dual-port test mode(S21),respectively.The results show that the quality factor of the device is 51.29 and the 3 dB bandwidth is 27.8 MHz by S11-mode measurement,which is better than the S21 mode,and is consistent with the frequency response curve by simulation.