• Journal of the Korean Ceramic Society
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• v.46 no.1
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• pp.30-34
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• 2009

A Sand blasting technology has been used to address via and trench processing of glass wafer of optic semiconductor packaging. Manufactured sand blast that is controlled by blast nozzle and servomotor so that 8" wafer processing may be available. 10mm sq test device manufactured by Dry Film Resist (DFR) pattern process on 8" glass wafer of $500{\mu}m's$ thickness. Based on particle pressure and the wafer transfer speed, etch rate, mask erosion, and vertical trench slope have been analyzed. Perfect 500 um tooling has been performed at 0.3 MPa pressure and 100 rpm wafer speed. It is particle pressure that influence in processing depth and the transfer speed did not influence.

• Journal of Integrative Natural Science
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• v.2 no.1
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• pp.45-49
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• 2009

Electrochemical etching of heavily doped p-type silicon wafers (boron doped, <100> orientation, resistivity; $0.8-1.2m{\Omega}/cm$) with different current density resulting two different refractive indices resulted in DBR (Distributed Bragg Reflectors) porous silicon, which exhibited strong in-plane anisotropy of refractive index (birefringence). Dielectric stacks of birefringent porous silicon acting as distributed Bragg reflectors have two distinct reflection bands depending on the polarization of the incident linearly polarized light. This effect is caused by a three-dimensional (in plane and in depth) variation of the refraction index. Optical characteristics of DBR porous silicon were investigated.

• Journal of the Korean Institute of Telematics and Electronics A
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• v.33A no.4
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• pp.112-120
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• 1996

With the MOsES (mask oxide sidewall etch scheme)process which uses the conventional i-line stepper and isotropic wet etching, CMOSFET's with fine gate pattern of 0.1.mu.m CMOSFET device, the screening oxide is deposited before the low energy ion implantation for source/drain extensions and two step sidewall scheme is adopted. Through the characterization of 0.1.mu.m CMOSFET device, it is found that the screening oxide deposition sheme has larger capability of suppressing the short channel effects than two step sidewall schem. In cse of 200.angs.-thick screening oxide deposition, both NMOSFET and PMOSFET maintain good subthreshold characteristics down to 0.1.mu.m effective channel lengths, and show affordable drain saturation current reduction and low impact ionization rates.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.16 no.4
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• pp.280-285
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• 2003

The influence of silicon surface damage on nickel-silicide (NiSi) has been characterized and H$_2$ anneal and TiN rapping has been applied to suppress the electrical, morphological deterioration phenomenon incurred by the surface damage. The substrate surface is intentionally damaged using Ar IBE (Ion beam etching) which can Precisely control the etch depth. The sheet resistance of NiSi increased about 18% by the surface damage, which is proven to be mainly due to the reduced silicide thickness. It is shown that simultaneous application of H: anneal and TiN capping layer is highly effective in suppressing the surface damage effect.

• Journal of the Korean Society for Precision Engineering
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• v.22 no.9 s.174
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• pp.60-68
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• 2005

To investigate the effects of beam focusing in the etching of polymers with short pulse Excimer lasers, a polymer etching model of SSB's is combined with a beam focusing model. Through the numerical simulation, it was found that in the high laser fluence region, SSB model considering both photochemical and thermal contribution is considered to be suitable to predict the etched hole shape than a simple photochemical etching model. The average temperature distribution into the substance obtained by assuming 1-D heat transfer is found to be fairly similar to the fluence distribution on the ablated surface. The experimental etching data fur polymers are used to give material properties for ablation model. The fitted etch depth curve gives a nice agreement with the experimental data.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2006.05a
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• pp.659-660
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• 2006

High-aspect-ratio(max. 12.5) microchannels with excellent surface quality and good shape uniformity have been realized utilizing laser-induced etching technique. Etch width and depth variations depend largely upon process variables such as laser power and etchant concentration. Etchant concentration in association with viscosity also influence on the cross-sectional profile of the channels. The optimum process conditions for the fabrication of high-aspect-ratio microchannels applicable to micro thermal devices are demonstrated.

• 한국정보디스플레이학회:학술대회논문집
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• 2003.07a
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• pp.1038-1041
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• 2003

In the paper, we investigated silicon surface microstructures formed by reactive ion etching in hollow cathode system. Wet anisotropic chemical etching technique use to form random pyramidal structure on <100> silicon wafers usually is not effective in texturing of low-cost multicrystalline silicon wafers because of random orientation nature, but High density hollow cathode plasma system illustrates high deposition rate, better film crystal structure, improved etching characteristics. The etched silicon surface is covered by columnar microstructures with diameters form 50 to 100nm and depth of about 500nm. We used $SF_{6}$ and $O_{2}$ gases in HCP dry etch process. This paper demonstrates very high plasma density of $2{\times}10^{12}$ $cm^{-3}$ at a discharge current of 20 mA. Silicon etch rate of 1.3 ${\mu}s/min$. was achieved with $SF_{6}/O_{2}$ plasma conditions of total gas pressure=50 mTorr, gas flow rate=40 sccm, and rf power=200 W. Our experimental results can be used in various display systems such as thin film growth and etching for TFT-LCDs, emitter tip formations for FEDs, and bright plasma discharge for PDP applications. In this paper we directed our study to the silicon etching properties such as high etching rate, large area uniformity, low power with the high density plasma.

• Journal of Sensor Science and Technology
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• v.3 no.3
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• pp.45-53
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• 1994

A new type of Si diaphragm was fabricated using Si-wafer direct bonding and two-step electrochemical etch-stopping methods. Using the new diaphragm structure in mechanical sensors, more precise control of cavity depth and diaphragm thickness was achievable. Also, the propagation of the stress, which was generated near the bonding interface, to the surface can be avoided. Finally, a piezoresistive-type Si pressure sensor was fabricated utilizing the diaphragm and a digital pressure gauge, which can display units of pressure, was realized.

• Journal of the Korean Chemical Society
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• v.44 no.3
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• pp.200-206
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• 2000

The metal impurities in specific regions at near surface of silicon wafer were determined by constant depth etching·lt is possible to etch uniformly over the entire wafer surface by 1$\mu\textrm{m}$ depth with 5 mL of etching solution made up of HF and HNO$_3$ mixed by l:3 volume ratio. The microwave oven was used to evaporate the solution after etching. After spiking, The recoveries of Cu, Ni, Zn, Cr, Mg and K were found to be 99∼105%ted in polysilicon region and could be quantified by 1$\mu\textrm{m}$ depth.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1995.05a
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• pp.58-61
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• 1995

Instead of using CCl$_4$CCl$_2$F$_2$ gases, we used a alternative reaction gas of CFCs which we have developed, for the experiment of laser induced dry etching of laser induced dry etching of GaAs, and compared with the etch profile of a usual reation gas. Laser powers(power density) on the sample surface were varied from 100 mW(12.7 MW/$\textrm{cm}^2$) to 210mW(27 MW/$\textrm{cm}^2$) The laser beam was scanned over the sample by moving the cell with a speed raging from 8.3$\mu\textrm{m}$/sec and the gas pressure also was varied form 260 Torr to 760 Torr, High etching rates up to 136 $\mu\textrm{m}$/sec and an aspect ratio of 2.6 have been achieved by single scan of laser beam. The chemical compositions of the reaction products deposited on the etched groove were measured by Auger electron spectroscopy(AES) Etch profiles, including depth and width were observed by scanning electron microscopy(SEM)