• Title/Summary/Keyword: Quartz substrate

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Frequency Agile Properties of Microstrip Antenna Using Quartz (Quartz를 이용한 마이크로스트립 안테나의 주파수 특성에 관한 연구)

  • 하용만;오승재;우형관;송준태
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2001.11a
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    • pp.488-491
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    • 2001
  • This paper investigated that resonant frequencies of microstrip patch antenna were agile when piezoelectric materials were used as the antenna substrates. The resonant frequencies of the microstrip antenna using the piezoelectric substrate. The microstrip patch antenna made of Quartz substrate was designed and fabricated by Ensemble v 7.0 simulator. The experimental problem was compensated by Ensemble v 7.0

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Frequency Agile Properties of Microstrip Antenna Using Quartz (안테나의 주파수 특성에 관한 연구)

  • Yun, Chang-Jin;Ha, Yong-Man;Hwang, Hyun-Suk;Song, Joon-Tae
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2002.07b
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    • pp.715-718
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    • 2002
  • This paper investigated that resonant frequencies of microstrip patch antenna were agile when piezoelectric materials were used as the antenna substrates. When the bias is applied on them, thickness of the substrate is varied according. to the piezoelectric phenomenon. The microstrip patch antenna using Quartz substrate was fabricated and designed by Ensemble v 7.0 simulator. We fabricated the microstrip antennas using Quartz(Y-cut) as its substrate. When the operating frequencies of the microstrip antenna were 7.045GHz, 7.773GHz 8.18GHz the frequency shifts versus electric field, Emax=4[kV/cm], were 21MHz, 26MHz and 28MHz, respectively.

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Accurate Measurement of THz Dielectric Constant Using Metamaterials on a Quartz Substrate

  • Park, Sae June;Ahn, Yeong Hwan
    • Current Optics and Photonics
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    • v.1 no.6
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    • pp.637-641
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    • 2017
  • We present dielectric constant measurements of thin films using THz metamaterials fabricated on a quartz substrate. The resonance shifts of the metamaterials exhibit saturation behavior with increasing film thickness. The saturation frequency shift varies with the real part of the dielectric constant, from which the numerical expression for the particular metamaterial design was extracted. We first performed finite-difference time-domain simulations to find an explicit relationship between the saturated frequency shift and the dielectric constant of a thin film, which was confirmed by the experimental results from conventional techniques. In particular, the quartz substrate enables us to determine their values more accurately, because of its low substrate index. As a result, we extracted the dielectric constants of various films whose values have not been addressed previously without precise control of the film thickness.

A Novel Stiff Membrane Seesaw Type RF Microelectromechanical System DC Contact Switch on Quartz Substrate

  • Khaira, Navjot K.;Singh, Tejinder;Sengar, Jitendra S.
    • Transactions on Electrical and Electronic Materials
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    • v.14 no.3
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    • pp.116-120
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    • 2013
  • This paper proposes a novel RF MEMS dc-contact switch with stiff membrane on a quartz substrate. The uniqueness of this work lies in the utilization of a seesaw mechanism to restore the movable part to its rest position. The switching action is done by using separate pull-down and pull-up electrodes, and hence operation of the switch does not rely on the elastic recovery force of the membrane. One of the main problems faced by electrostatically actuated MEMS switches is the high operational voltages, which results from bending of the membrane, due to internal stress gradient. This is resolved by using a stiff and thick membrane. This membrane consists of flexible meanders, for easy movement between the two states. The device operates with an actuation voltage of 6.43 V, an insertion loss of -0.047 dB and isolation of -51.82 dB at 2 GHz.

Frequency Agile Properties of Microstrip Antenna Using Quartz (Quartz를 이용한 마이크로스트립 안테나의 주파수 특성에 관한 연구)

  • Ha, Yong-Man;Oh, Seung-Jae;Woo, Hyoung-Gwan;Song, Joon-Tae
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2001.11b
    • /
    • pp.488-491
    • /
    • 2001
  • This paper investigated that resonant frequencies of micro strip patch antenna were agile when piezoelectric materials were used as the antenna substrates. The resonant frequencies of the micro strip antenna using the piezoelectric substrate. The micro strip patch antenna made of Quartz substrate was designed and fabricated by Ensemble v 7.0 simulator. The experimental problem was compensated by Ensemble v 7.0

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Analysis of resonant frequency in microstrip antennas using X-cut Quartz plates (X-cut quartz를 이용한 마이크로스트립 안테나의 해석)

  • Kang, Hyun-Il;Hwang, Hyun-Suk;Lee, Kyu-Il;Lee, Tae-Yong;Song, Joon-Tae
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2006.06a
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    • pp.380-381
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    • 2006
  • A technique to control the operating frequency of microstrip antenna by using the X-cut quartz substrate has been investigated experimentally and theoretically. We consider 6, 8 and 10 GHz resonance frequency in three dimensional quartz plates. Equation of linear piezoelectricity are solved for the thickness-shear approximation of X-cut quartz plates. At X-band frequencies, the microstrip antenna was voltage-controllable using the dc electric field dependence of the piezoelectric constant of X-cut quartz. This work demonstrates advantageous application for X-cut quartz plate in microstrip antenna substrates.

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Controlling of the heterogeniously growing GaN polycrystals using a quartz ring in the edge during the HVPE-GaN bulk growth

  • Park, Jae Hwa;Lee, Hee Ae;Park, Cheol Woo;Kang, Hyo Sang;Lee, Joo Hyung;In, Jun-Hyeong;Lee, Seong Kuk;Shim, Kwang Bo
    • Journal of Ceramic Processing Research
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    • v.19 no.5
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    • pp.439-443
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    • 2018
  • The outstanding characteristics of high quality GaN single crystal substrates make it possible to apply the manufacture of high brightness light emitting diodes and power devices. However, it is very difficult to obtain high quality GaN substrate because the process conditions are hard to control. In order to effectively control the formation of GaN polycrystals during the bulk GaN single crystal growth by the HVPE (hydride vapor phase epitaxy) method, a quartz ring was introduced in the edge of substrate. A variety of evaluating method such as high resolution X-ray diffraction, Raman spectroscopy and photoluminescence was used in order to measure the effectiveness of the quartz ring. A secondary ion mass spectroscopy was also used for evaluating the variations of impurity concentration in the resulting GaN single crystal. Through the detailed investigations, we could confirm that the introduction of a quartz ring during the GaN single crystal growth process using HVPE is a very effective strategy to obtain a high quality GaN single crystal.

Role of Metal Catalyst and Substrate Site for the Growth of Carbon Nanomaterials

  • Manocha, L.M.;Valand, Jignesh;Manocha, S.
    • Carbon letters
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    • v.6 no.2
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    • pp.79-85
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    • 2005
  • The work reported in this paper relates to preparation and characterization of carbon nanomaterials by CVD method on different substrates by decomposition of certain hydrocarbons at 550-$800^{\circ}C$ using a horizontal quartz tube reactor. Monometallic and bimetallic catalyst system of iron and nickel were used for the preparation of different carbon nanomaterials. The influence of various parameters such as substrate/catalyst preparation parameters, the nature of substrate, catalyst concentration, reaction time and temperature on the growth, yield and alignment of carbon nanotubes has been studied. The characterization of carbon nanomaterials has been carried out using SEM, TEM and TGA. The carbon nanomaterials developed were vertically aligned on a large area of flat quartz substrate.

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Stress Analysis Using Finite Element Modeling of a Novel RF Microelectromechanical System Shunt Switch Designed on Quartz Substrate for Low-voltage Applications

  • Singh, Tejinder;Khaira, Navjot K.;Sengar, Jitendra S.
    • Transactions on Electrical and Electronic Materials
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    • v.14 no.5
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    • pp.225-230
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    • 2013
  • This paper presents a novel shunt radio frequency microelectromechanical system switch on a quartz substrate with stiff ribs around the membrane. The buckling effects in the switch membrane and stiction problem are the primary concerns with RF MEMS switches. These effects can be reduced by the proposed design approach due to the stiffness of the ribs around the membrane. A lower mass of the beam and a reduction in the squeeze film damping is achieved due to the slots and holes in the membrane, which further aid in attaining high switching speeds. The proposed switch is optimized to operate in the k-band, which results in a high isolation of -40 dB and low insertion loss of -0.047 dB at 21 GHz, with a low actuation voltage of only 14.6 V needed for the operation the switch. The membrane does not bend with this membrane design approach. Finite element modeling is used to analyze the stress and pull-in voltage.

Solution growth of polycrystalline silicon on Al-Si coated borosilicate and quartz glass substrates for low cost solar cell application (저가태양전지에 응용을 위한 용액성장법에 의한 Al-Si층이 코팅된 유리기판상의 다결정 실리콘 박막성장에 관한 연구)

  • Lee, S.H.;Queisser, H.J.
    • Journal of the Korean Crystal Growth and Crystal Technology
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    • v.4 no.3
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    • pp.238-244
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    • 1994
  • We investigated solution growth of silicon on borosilicate and quartz glass substrates in the temperature range of $800^{\circ}C~520^{\circ}C$. A thin Al-Si layer evaporated onto the substrate serves to improve the wetting between the substrate and the Al/Ga solvent. Nucleation takes place by a reaction of Al with $SiO_2$ from the substrate. We obtained silicon deposits with a grain size up to a few 100 $\mu\textrm{m}$. There was a perferential (111) orientation for the case of quartz glass substrates while there is a strong contribution of other orientations for the deposition of Si on borosilicate glass substrates.

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