We investigated the variation of anion exchange membrane of hydrogen generator of alkaline electrolysis. We detected the variation of elements and change of anion exchange membrane using EDS and FE-SEM. We detected two different sites of membrane because of different structure of membrane. Sp2 shows that the distribution ratio of C, 0, Al is 98% very higher than Sp2 of 78%. Especially, the main elements of STS316 which is P. S. Fe, Ni were more detected at Sp2 than Sp,. We think that this result depends on the structure of membrane. This also affect the resistance, lifetime of membrane and decrease the efficiency of hydrogen production. We hope that this article is a foundation of developing of hydrogen production technology.

In this paper, We studied the change of surface and variation of elements on both electrodes of hydrogen generator of alkaline electrolysis in use of FE-SEM and SIMS. We used the stainless steel 316(6(X) p m) as electrode in condition of 25%KOH, 60℃ Temperature. The results show that the intensity of elements (C, Si, P. S. Ti, Cr, Mn, Fe, Ni, Mo) of Positive Electrode are decreased as much as about 101 than the original electrode. Thickness of Positive Electrode is decreased about 40 pin after chemical reaction. The negative electrode, however, shows a slight variation in the intensity of elements (C, Si, P. Fe, Ni, Mn, Mo) but Change of thickness and surface` shape of electrode show nothing after chemical reaction. The change in thickness and variation of Stainless Steel 316 cause the lifetime of electrode to be shorted. We also observed hydrogen. oxygen, potassium in both electrodes. Especially, The potassium is increased in proportional with depth of positive electrode. this means the concentration of alkali solutions is changed. and so we have to supply alkaline solution to generator in order to produce same quantity of hydrogen gas continuously, we hope that this study gives a foundation to develop the electrode for hydrogen generator of alkaline electrolysis.

Due to the high etch rate and low fabrication cost, the wet etching of silicon using KOH etchant is widely used in MEMS fabrication area. However, anisotropic etch characteristic obstruct intuitional mask design and compensation structures are required for mask design level. Therefore, the accurate modeling for various types of silicon surface is essential for fabrication of three-dimensional MEMS structure. In this paper, we modeled KOH etch profile for MEMS based energy harvester using fuzzy logic. Modeling results are compared with experimental results and it is applied to design of compensation structure for MEMS based energy harvester. Through Fuzzy inference approaches, developed model showed good agreement with the experimental results with limited etch rate information.

The morphology of etch pits in commercial 4H-SiC epi-wafer were investigated by molten-KOH etching. The etching process was optimized in 525~570℃ at 2~10 min and the novel type of etch pits was revealed. This type of etch pits have been considered as TED (threading edge dislocation) II, its origin and nature, however, are not reported yet. In this work, the morphology and evolution of etch pits during epitaxial growth were analyzed and the different behavior between TED and TEDII was discussed.

The present study introduces a novel wet etching technique for nanostructure fabrications which usually requires low surface roughness. Using the current method, acquired profiles were smooth even in the nanoscale, which cannot be easily achieved with conventional wet or dry etching methods. As one of the most popular single crystal silicon etchant, potassium hydroxide (KOH) solution was used as a base solvent and two additives, antimony trioxide (Sb2O3) and ethyl alcohol were employed in. Four experimental parameters, concentrations of KOH, Sb2O3, and ethyl alcohol and temperature were optimized at 60 wt.%, 0.003 wt.%, 10 v/v%, and 23℃, respectively. Effects of additives in KOH solution were investigated on the profiles in both (110) and (111) planes of single crystal silicon wafer. The preliminary results show that additives play a critical role to decrease etch rate significantly down to ~2 nm/min resulting in smooth side wall profiles on (111) plane and enhanced surface roughness.