This study investigates the effect of mask material and thickness on the silicon etching profile using a high-density plasma (HDP) etching system, aiming to reduce optical loss in silicon-based optical waveguides. As the mask thickness increased, the etching sidewall angle became steeper. An etching profile angle of 87° was obtained when tetraethyl orthosilicate (TEOS) was used as the mask material, while 80° was obtained for photoresist (PR). This is attributed to electron charging on the mask surface in the plasma. The charged mask modifies the distribution and strength of the electric field depending on its thickness, thereby affecting the trajectory of positive ions accelerated toward the substrate by the bias voltage. Furthermore, Plasma diagnostics using optical emission spectroscopy (OES) and surface composition analysis using field emission Auger electron spectroscopy (FE-AES) revealed that changes in the mask material also alter the reaction pathways and formation characteristics of active species and silicon by-products in the plasma. These results suggest that the mask material influences the overall plasma characteristics, including electron density and ion energy, and plays a critical role in the precise control of silicon etching profiles for high-performance optical device fabrication.
Inductively coupled plasma reactive ion etching (ICP-RIE) of copper thin films patterned with SiO2 hard masks was carried out using piperidine/O2/Ar gas mixture. The etch rate, etch selectivity, and etch profile of copper thin films were investigated by varying gas concentration in piperidine/O2/Ar gas mixture. In addition, the etch parameters including ICP RF power, DC-bias voltage to substrate, and process pressure were varied to examine the etch characteristics. X-ray photoelectron spectroscopy and optical emission spectroscopy were employed to elucidate the etch mechanism under piperidine/O2/Ar gas chemistry. Finally, 150 nm-line patterned copper thin films were successfully etched using piperidine/ O2/Ar etch gas under the optimized etch conditions.
In this study, image analysis and surface roughness measurements using an optical microscope are presented as a method to quantitatively evaluate the results of screen printing. Using this method, the squeegee speed, which is the printing process condition, and the printability of the electrode according to the screen mesh were evaluated. Increasing the squeegee speed in the printing process acts as a process element that increases the line width precision of the printed electrode and lowers the surface roughness of the printed surface. Furthermore, the edge roughness, which indicates the clarity of printing, was not significantly affected by the speed of the squeegee during printing. The print thickness increases in proportion to the squeegee speed, but is largely dependent on the screen thickness.
Sound Masking System technology as by sound the same on all bands and artificially generates a constant sound shield People want to hear or recognize the people with the noise generated from the interior of the way. Prevent hearing or prevent recognition by using the technology to control the audible frequency band Continue to emit constant and uniform shielding sound audible frequency band Even the security content of speech (20 Hz ~20 KHz). That interception laser eavesdropping, internal solicitations, during recording Or delay the decoding was a result of the effect of interference calculated Experience noise disturbance index is applied around the Stress Index is the average index is 10.16 was a luxury for the average index is then applied to the index 3.07 Noise is significantly lower stress level has improved noise conditions.
A Study on the CFD Analysis of Jig Modules in Hybrid BGA Systems for Semiconductor Packaging Processes Ju-Ran Choi, Seong-Hyun Kim, Seong-Dae Choi Journal of the Korean Society of Manufacturing Process Engineers.2026; 25(6): 49. CrossRef
A Study on Optical Efficiency Improvement of LED-Lighting Adopting Aspherical Optical System(1) Hak Suk Lee, Jong Rak Park, Min Jae Kim, Hye Jeong Kim, Jeong Ho Kim Journal of Korean Institute of Electrical and Electronic Materials Engineers.2009; 22(12): 1033. CrossRef