• 반도체디스플레이기술학회지
• /
• 제13권2호
• /
• pp.29-35
• /
• 2014

In this study general solar cell production process was complemented, with research on improvement of solar cell efficiency through surface structure and thermal annealing process. Firstly, to form the pyramid structure, the saw damage removal (SDR) processed surface was undergone texturing process with reactive ion etching (RIE). Then, for the formation of smooth pyramid structure to facilitate uniform doping and electrode formation, the surface was etched with HND(HF : HNO3 : D.I. water=5 : 100 : 100) solution. Notably, due to uniform doping the leakage current decreased greatly. Also, for the enhancement and maintenance of minority carrier lifetime, antireflection coating thermal annealing was done. To maintain this increased lifetime, front electrode was formed through Au plating process without high temperature firing process. Through these changes in two processes, the leakage current effect could be decreased and furthermore, the conversion efficiency could be increased. Therefore, compared to the general solar cell with a conversion efficiency of 15.89%, production of high efficiency solar cell with a conversion efficiency of 17.24% was made possible.

• 한국표면공학회지
• /
• 제41권1호
• /
• pp.6-11
• /
• 2008

An Indium Zinc Oxide(IZO) transparent conductive layer was deposited on a large size glass substrate by using magnetron dc sputtering method with varying a deposition temperature. As the deposition temperature decreased to a room temperature, the sheet resistance of IZO film increased. But this deposition temperature range is included in an applicable to a device. From a standpoint of the sheet resistance, the differences of the sheet resistance were not great and the uniformity of the layer was uniformed around 10%. Crystallization particles were shown on the surface of the layer as deposition temperature increased, but these particles were not shown on the surface of the layer as deposition temperature decreased to the room temperature. It didn't make a scrap of difference in a transmittance of varying deposition temperature. Therefore, it is concluded that IZO thin film manufactured by the room temperature deposition condition can be used as a large size transparent conductive layer of a liquid crystal display device.

• 반도체디스플레이기술학회지
• /
• 제19권2호
• /
• pp.45-50
• /
• 2020

We investigated the Si_1-xGe_x surface properties when dry cleaning the films using NF₃ / H₂O remote plasma. After the dry cleaning process, it was found that about 80-250 nm wide bumps were formed on the SiGe surface regardless of Ge concentration in the rage of x = 0.1 ~ 0.3. In addition, effects of the dry cleaning processing parameters such as pressure, substrate temperature, and H₂O flow rates were examined. It was found that the surface bump is significantly dependent on the flow rate of H₂O. Based on these observations, we would like to provide additional guidelines for implementing the dry cleaning process to SiGe materials.

• Journal of Information Display
• /
• 제4권2호
• /
• pp.29-34
• /
• 2003

We have studied liquid crystal (LC) molecular alignment on rubbed and photoaligned surfaces. Particular attention was paid to the intermolecular liquid crystalline interaction. We will first show that uniform molecular orientation on a rubbed surface does not mean spatially uniform interaction between the surface and LC molecules. Rather LCs tend to align themselves through LC interaction. The existence of nonuniformity of rubbing was successfully visualized by double surface treatment. The importance of intermolecular LC interaction was also found in the orientation formation process in 5CB evaporated on rubbed and photoaligned surfaces. By simultaneously analyzing polarized UVNIS absorption and second-harmonic generation (SHG) using the maximum entropy method, we succeeded in obtaining the temporal variation of the orientational distribution functions in the film forming process. The distribution anisotropy and pretilt are found to be generated under the influence of intermolecular LC interaction.

• Transactions on Electrical and Electronic Materials
• /
• 제1권4호
• /
• pp.20-24
• /
• 2000

This study aimed to develop ITO(Indium Tim Oxide) tin films ablation with a pulsed type KrF excimer laser required for the electrode patterning application in flat panel display into small geometry on a large substrate are. The threshold fluence for ablating ITO on glass substrate is about 0.1 J/㎠. And its value is much smaller than that using 3 .sup rd/ harmonic Nd:YAG laser. Through the optical microscope measurement the surface color of the ablated ITO is changed into dark brown due to increase of surface roughness and transformation of chemical composition by the laser light. The laser-irradiated regions were all found to be electrically isolating from the original surroundings. The XPS analysis showed that the relative surface concentration of Sn and In was essentially unchanged (In:Sn=5:1)after irradiating the KrF excimer laser. Using Al foil made by 2$\^$nd/ harmonic Na:YAG laser, the various ITO patterning is carried out.

• Design & Manufacturing
• /
• 제11권2호
• /
• pp.42-45
• /
• 2017

Currently, the mobile device is required to be miniaturized and lightweight according to the needs of the consumer. For this purpose, each part is produced and assembled in units of modules. Accordingly, the display part is also composed of a cover glass, a touch screen, And it costs a large amount to replace the whole when it is damaged. Therefore, we propose a method to improve the durability of display part using ANOVA (Analysis of Variance) and MR fluid polishing. Before MR fluid polishing process, surface treatment was performed to obtain a polishable surface. A series of experiments were carried out to very fine surface roughness and to secure durability of cover glass. Polishing depth, feed rate, and abrasive size were selected to examine the MR fluid polishing results.

• 반도체디스플레이기술학회지
• /
• 제18권2호
• /
• pp.44-47
• /
• 2019

Amorphous carbon layer (ACL) is actively used as an etch mask. Recent advances in patterning ACL requires the next level of durability of hard mask in high aspect ratio etch in near future semiconductor manufacturing, and it is worthwhile to know the surface property of ACL thin film to enhance the property of etch hard mask. In this research, ACL are deposited by 6 inch plasma enhanced chemical vapor deposition system with $C_3H_6$ and $N_2$ gas mixture. Surface properties of deposited ACL are investigated depending on gas flow, pressure, RF power. Fourier transform infrared is used for the analysis of surface chemistry, and X-ray photoemission spectra is used for the structural analysis with the consideration of the contents of $sp^2$ and $sp^3$ through fitting of C1s. Also mechanical properties of deposited ACL are measured in order to evaluate hardness.

• 반도체디스플레이기술학회지
• /
• 제18권1호
• /
• pp.117-122
• /
• 2019

Pipes are widely used in various industries such as automobile, anti-vibration devices, factories and ship building. Chamfering is one of the most critical processes in pipe manufacturing which removes burrs of the pipes for better surface quality. In most cases, the defects of the chamfered surface are originated from the structural vibrations of the chamfering machine. In this study, the dynamic characteristics of a chamfering machine have been analyzed though the experiment and the computer simulation. And the effects of the design parameters affecting the stability of the machine have been investigated to stabilize the machine structure and further to reduce structural vibrations. The result shows that design alterations to stabilize the machine can suppress the defects of the machined surface as well as the vibrations during chamfering.

• 반도체디스플레이기술학회지
• /
• 제20권1호
• /
• pp.12-17
• /
• 2021

The electronic and magnetic properties for Mn-adsorbed on the chalcopyrite (CH) AlGaP2 semiconductor are investigated by using first-principles FPLMTO method. The clean CH-AlGaP2 without adsorbed Mn is a p-type semiconductor with a direct band-gap. The Mn-adsorbed CH-AlGaP2 exhibits the ferromagnetic state. It is more energetically stable than the other magnetic ones. The interstitial site on P-terminated surface is more energetically favorable one than the Al/Ga-terminated surface, or the other adsorbing sites. In the case of Mn-adsorbed Al/Ga-terminated surface, it is induced a strong coupling between Mn-3d and neighboring P-3p electrons. The holes of partially unoccupied minority Mn-3d state and majority (or minority) Al-3p or P-3p state are induced. Thus a high magnetic moment of Mn is sustained by holes-mediated double-exchange coupling. It is noticeable that the semiconducting and half-metallic characteristics of CH-AlGaP2:Mn thin film is disappeared.

• 한국전기전자재료학회논문지
• /
• 제23권9호
• /
• pp.691-695
• /
• 2010

A measurement method of the particle-based reflective display is proposed, estimated, and compared with reported method. The reflectivity measurement by previous studies is simply obtained by integrating sphere, but it has a limitation for the estimation of real moving particles because its data include surface reflection and incomplete attachment on electrodes. To get the number of real moving particles, the area by attached particles on the electrodes is calculated at microscopic signals. The moving particles on subthreshold voltage are observed and this fluctuational variation of surface on subthreshold voltage gives a tip to understand the driving mechanism. By this measurement we ascertained the relationship of a particle layer and real driving particles, and the feasibility of observation and estimation for moving color particles, which were measured by the reflectivity and CIE (Commission Internationale de I'Eclairage) system of color specification at previous studies.