Micropattern transfer without photolithography of substrate :Ni electrodeposition using enface technology

PhD ThesisSince the standard photolithographic patterning technology possesses a number of sustainable issues, a “maskless” technology, Enface, has been proposed. Here, a patterned ‘tool’ placed opposite to the substrate within micrometre range is required. Etching or plating occurs by passing tailored current or voltage waveforms, provided that the electrolyte resistance is high. Enface is a resource efficient process as the use of chemicals is greatly reduced. This research project aimed to investigate the feasibility of Ni pattern transfer using Enface under stagnant conditions. It would be advantageous if Enface could be used for nickel deposition as it is a slow kinetic system and controlled by mixed mass transfer and kinetics which is a system where Enface has never been used before. An electrochemical cell has been specifically designed and an electrolyte was systemically developed as required by Enface. Polarisation experiments were carried out to determine applied current densities that would be used in galvanostatic plating experiments for pattern transfer of millimetre and micron scale features. Deposited features were comprehensively characterised to see the performance of the patterning process. Current distribution during the pattern transfer experiments was investigated by simulation and modelling using Elsy software. An electrolyte of 0.19 M nickel sulfamate was selected and shown to be capable of depositing nickel. Polarisation data from experiments in Enface system showed that each feature size requires a different applied current density. As expected, pattern transfers of metallic nickel were achieved for millimetre and micron scale features at a current efficiency of around 90 % with current spreading were observed. The deposited feature width broadens with increasing time and decreasing feature size. In addition, maximum thickness that could be achieved was around 0.5 μm due to entrapped gas bubbles leading to process termination. The gas bubbles were detrimental to the deposits resulting in a rough and inhomogeneous surface as well as photoresist degradation. Ultrasound agitation was shown to be capable of diminishing the effect of gas bubbles. However it requires an optimisation of applied power density to avoid negative effects of cavitation bubbles. The result of simulation showed a non-uniform current distribution across the feature width with the highest current density at the centre resulting in a bell-shaped surface profile which is in agreement with the experiments. However, the deposited shape evolution obtained from the experiments is consistently much better than those obtained from the simulation.Ministry of Education and Culture through Directorate General for Higher Education, Government of Republic of Indonesia for funding my PhD study, Poc-Enface for research studentshi

Pengaruh Waktu Pemasakan dan Konsentrasi NaOH Terhadap Penurunan Kadar Lignin Pulp dari Batang Pisang Kepok dengan Proses Soda

Banana is a plant that has very high cellulose content so it can be used as a raw material for making pulp. This research was conducted with the aim of knowing the effect of cooking time and sodium hydroxide concentration on reducing the lignin content of banana stem pulp by soda process. The cooking solution used in the soda process is NaOH solution. With various concentrations of NaOH 20%, 25%, and 30% and cooking time 40, 80, and 120 minutes. The highest lignin content was 1.8785% during pulping for 40 minutes with 20% NaOH concentration. While the lowest lignin content was 1.3093% during pulping for 120 minutes with 30% NaOH concentration

Pengaruh Konsentrasi Kapang dan Lama Waktu Fermentasi terhadap Kadar Bioetanol dari Limbah Kulit Singkong (Manihot esculenta)

The purpose of this research is the manufacture of bioethanol by utilizing cassava peel, this process is through acid hydrolysis and fermentation processes. Making bioethanol with variations in the effect of the rate of fermentation time (5th days and 10th days), as well as with variations in the amount of mold concentrations (10%, 20%, and 30%). The mold used is Saccharomyces cerevisiae, then the mixed bioethanol is separated through the distillation process and will produce bioethanol. Based on the data obtained, the highest ethanol content was found in the variation of the addition of 30% mold on the 5th day of 8.09% and the lowest ethanol content was found in the variation of the addition of 10% mold on the 10th days of 5.86%. This proves that each variation has an optimum value in producing bioethanol content from cassava peels

Initial Study of Nickel Electrolyte for EnFACE Process

Nickel electrolyte for a micro-pattern transfer process without photolithography, EnFACE, has been developed. Previous work on copper deposition indicated that a conductivity of ~2.7 Sm-1 is required. Electrochemical parameters of electrolyte i.e. current density and overpotential are also crucial to govern a successful pattern replication. Therefore, the investigation focused on the measurement of physicochemical properties and electrochemical behaviour of the electrolyte at different nickel concentrations and complexing agents of chloride and sulfamate. Nickel electrolytes containing sulfamate, chloride and combined sulfamate-chloride with concentrations between 0.14 M and 0.3 M were investigated. Physicochemical properties i.e. pH and conductivity were measured to ensure if they were in the desired value. The electrochemical behaviour of the electrolytes was measured by polarisation experiments in a standard three-electrode cell. The working electrode was a copper disc (surface area of 0.196 cm2) and the counter electrode was platinum mesh. The potential was measured againts a saturated calomel reference electrode (SCE). The experiments were carried out at various scan rate and Rotating Disc Electrode (RDE) rotation speed to see the effect of scan rate and agitation. Based on the measured physicochemical properties, the electrolyte of 0.19 M nickel sulfamate was chosen for experimentation. Polarisation curve of agitated solution suggested that overall nickel electrodeposition reaction is controlled by a combination of kinetics and mass transfer. Reduction potential of nickel was in the range of -0.7 to -1.0 V. The corresponding current densities for nickel deposition were in the range of -0.1 to -1.5 mA cm-2

Pengaruh Waktu Ekstraksi dan Perbandingan Bahan Baku Pewarna Alami Daun Alpukat dan Daun Sirsak

This study explores the use of natural dyes as an environmentally friendly alternative to synthetic dyes for coloring batik fabric. Specifically, the researchers focus on developing natural dyes from a combination of avocado leaves and soursop leaves. The study aims to determine the impact of extraction time and the ratio of avocado and soursop leaves on the color fastness of batik cloth. Experimental methods were employed, with two extraction times (120 and 240 minutes) and three ratios of raw materials (25%:25%, 15%:35%, and 35%:15%) tested. The results of the color fastness test, which assessed washing and rubbing, demonstrated that the mixture of avocado and soursop leaves exhibited good fastness and resistance to rubbing. These findings suggest that the extracted mixture could be used effectively as a natural dye for batik fabric. Overall, this study contributes to the development of eco-friendly alternatives for the dyeing process in batik production

PENGARUH JENIS DAN KONSENTRASI ZAT FIKSASI PADA EKSTRAK DAUN MANGGA DALAM PEWARNAAN KAIN BATIK

The dyeing of batik cloth can use natural and synthetic dyes. The use of synthetic dyes in everyday life has an unfavorable effect on the environment, because it is carcinogenic. Therefore, it is necessary to make efforts to produce natural dyes that can replace synthetic repair materials. Manganese plants contain mangiferin pigments or flavonoid compounds which are used as natural dyes. The purpose of this study was to determine the effect of type and fixation concentration of mango leaf extract as a dye for batik cloth. This research method used a variety of alum and lime fixators with concentrations of 2%, 4% and 6%. the results showed that alum fixation gave a better fastness value than the fixation agent in lime with a concentration of 6% and the value of the test results was 4-5 which was at the good category, the results of the color difference test L*, a*, b* and identification of the color code and color light was done through encyclorpedia and the direction of the color produced from mango leaf extract showed a brown color in the fixation substances of alum and lime. Keywords: Mango Leaf, Fixation, Fastness, Natural Dye  AbstrakPewarnaan kain batik dapat menggunakan pewarna alami dan sintetis. Penggunaan pewarna sintetis dalam kehidupan sehari-hari memiliki efek tidak menguntungkan bagi lingkungan, karena bersifat karsinogenik. Oleh karena itu, perlu dilakukan upaya untuk menghasilkan pewarna alami yang dapat menggantikan bahan perbaikan sintetis. Tumbuhan mangga mengandung pigmen mangiferin atau senyawa flavonoid yang digunakan sebagai pewarna alami. Tujuan penelitian ini ingin mengetahui pengaruh jenis dan konsentrasi zat fiksasi pada ekstrak daun mangga sebagai pewarna kain batik. Metode penelitian ini menggunakan variasi bahan fiksasi tawas dan kapur dengan konsentrasi 2%, 4%, dan 6%, hasil penelitian menunjukkan bahwa fiksasi tawas memberikan nilai ketahanan luntur yang lebih baik dibandingkan zat fiksasi pada kapur dengan konsentrasi 6% dan nilai hasil uji 4-5 pada kategori baik, hasil uji beda warna L*,a*,b* dan identifikasi kode warna serta cahaya warna melalui encycolorpedia, arah warna yang dihasilkan dari ekstrak daun mangga menunjukkan warna coklat pada zat fiksasi tawas maupun kapur.Kata kunci: Daun Mangga, Fiksasi, Tahan Luntur, Pewarna Alam

PENGARUH FREKUENSI PENCELUPAN DAN JENIS MORDAN DARI EKSTRAK DAUN KETAPANG SEBAGAI PEWARNA ALAMI KAIN BATIK

Ketapang leaves contain tannin pigments of 11% -23% so that they can produce colors ranging from brownish yellow to dark brown. The purpose of this study was to determine how to process ketapang leaves into natural dyes for batik cloth and to determine the effect of dyeing frequency and type of mordant on color sharpness and color fastness. This study uses an experimental method, which is a method that is useful for finding the effect of certain treatments on the conditions to be controlled. The process starts from the selection of the extraction method, namely the reflux method, and the selection of the mordanting process, namely the provision of mordant at the end. The results showed that the effect of dyeing frequency and type of mordant on color sharpness using the L*, a*, b* color test was quite significant. The more the dyeing frequency, the darker the resulting color. The lowest L* value was 53.02 for lime mordant and 20.78 for tunjung mordant with 18 times of immersion frequency. The highest a* value was in lime mordant 12.15 with 18 times of immersion and 8.43 of tunjung mordant with 6 times of immersion. The highest b* value was 38.99 for lime mordant and 11.35 for tunjung mordant with 6 times of immersion frequency. The effect of the frequency of immersion and the type of mordant on the TLW test, namely washing soap and hot ironing dry did not have much significant effect. A good and optimal TLW value found in lime mordant and tunjung is 4 in the good category with 12 times the immersion frequency

Prarancangan Pabrik Asam Lemak Dari Minyak Kelapa Sawit Kapasitas 70.000 Ton/Tahun

Pengembangan perkebunan kelapa sawit di Indonesia berjalan sangat pesat karena merupakan komoditas yang berperan penting dalam pembangunan perekonomian Indonesia. Hasil pengolahan kelapa sawit sangat penting sebagai bahan baku berbagai industri kimia. Industri non pangan yang banyak menggunakan minyak kelapa sawit adalah industri oleokimia yang salah satu produknya adalah asam lemak. Kebutuhan asam lemak terus mangalami peningkatan. Oleh karena itu, didirikan Pabrik Asam Lemak dari Minyak Kelapa Sawit Kapasitas 70.000 ton/tahun yang dapat memenuhi kebutuhan dalam negeri dan luar negeri. Asam lemak diperoleh dari hidrolisis minyak (fat splitting). Proses hidrolisis yang digunakan adalah autoclave fat splitting, yaitu proses hidrolisis minyak yang beroperasi pada 140°C dan 1 atm selama 4 jam. Produksi asam lemak (99%) sebanyak 8.749,981 kg/jam membutuhkan bahan baku minyak kelapa sawit sebanyak 13.534,001 kg/jam ,air sebanyak 3.384,188 kg/jam dan katalis sebanyak 6,767 kg/jam. Utilitas meliputi penyediaan air proses 3.770,968 kg/jam (over design 20%), air untuk pendingin pada proses sebesar 663.719,188 kg/jam, air untuk kebutuhan steam sebesar 236.481,556 kg/jam yang diproduksi dari boiler dengan bahan bakar fuel oil sebesar 580.110,053 L/hari, air untuk sanitasi sebesar 2.508,000 kg/jam. Kebutuhan listrik sebesar 1.546,396 kW diperoleh dari PLN dan disediakan sebuah generator set sebagai cadangan. Kebutuhan udara tekan sebesar 101,52 m3/jam. Pabrik ini direncanakan didirikan di Rokan Hilir, Riau pada tahun 2020 dengan luas tanah 40.188 m2 dan memerlukan karyawan 200 orang. Pabrik Asam Lemak ini menggunakan modal tetap sebesar Rp.1.095.215.457.610,990 dan modal kerja sebesar Rp.242.156.770.790,760 Dari analisis ekonomi terhadap pabrik ini menunjukkan keuntungan sebelum dan sesudah pajak adalah Rp.408.289.773.487,540 dan Rp.285.802.841.441,278 Return on Investment (ROI) sebelum dan setelah pajak, 37,28 % dan 26,10%. Pay Out Time (POT) sebelum dan sesudah pajak, selama 2,115 tahun dan 2,770 tahun. Break Even Point (BEP) sebesar 40,51, Shut Down Point (SDP) sebesar 17,60%, Discounted Cash Flow (DCF) terhitung sebesar 41,641%. Dari data analisis kelayakan dapat disimpulkan, bahwa pabrik ini layak untuk didirikan