• 한국정밀공학회지
• /
• 제24권5호
• /
• pp.89-96
• /
• 2007

Inkjet printing has become one of the most attractive manufacturing techniques in industry. Especially inkjet printing technology will soon be part of the PCB (Printed Circuit Board) fabrication processes. Traditional printing on PCB includes screen printing and photolithography. These technologies involve high costs, time-consuming procedures and several process steps. However, by inkjet technology manufacturing time and production costs can be reduced, and procedures can be more efficient. PCB manufacturers therefore willingly accept this inkjet technology to the PCB industry, and are quickly shifting from conventional to inkjet printing. To produce the printed circuit board by the inkjet technology, it must be harmonized with conductive nano ink, printing process, system, and inkjet printhead. In this study, micro patterning of conductive line has been investigated using the piezoelectric printhead driven by a bipolar voltage signal is used to dispense 20-40 ${\mu}m$ diameter droplets and silver nano ink which consists of 1 to 50 nm silver particles that are homogeneously suspended in an organic carrier. To fabricate a conductive line used in PCB with high precision, a printed line width was calculated and compared with printing results.

• ETRI Journal
• /
• 제35권4호
• /
• pp.571-577
• /
• 2013

The fabrication of a thin-film transistor backplane and a liquid-crystal display using printing processes can eliminate the need for photolithography and offers the potential to reduce the manufacturing costs. In this study, we prepare contact via structures through a poly(methyl methacrylate) polymer insulator layer using inkjet printing. When droplets of silver ink composed of a polymer solvent are placed onto the polymer insulator and annealed at high temperatures, the silver ink penetrates the interior of the polymer and generates conducting paths between the top and bottom metal lines through the partial dissolution and swelling of the polymer. The electrical property of various contact via-hole interconnections is investigated using a semiconductor characterization system.

• 한국정밀공학회지
• /
• 제31권3호
• /
• pp.181-187
• /
• 2014

Micro patterns are used to maximize the performance and efficiency of the product in many industries such as energy, display, printing, biology, etc. Nowadays, the fabrication technology for micro patterns has been developed in various ways such as photolithography, laser machining, electrical discharge machining and mechanical machining. Recently, mechanical machining the size of smaller than 1 micrometer could be tried, because the technology related to the machining was developed brilliantly. This paper shows the experiments using cutting processes in order to fabricate the micro pattern. Micro patterns of the size of several micrometers were machined by the diamond tools of two different shape, the deformation and generation of burr were investigated.

• 대한전기학회:학술대회논문집
• /
• 대한전기학회 2007년도 Techno-Fair 및 추계학술대회 논문집 전기물성,응용부문
• /
• pp.98-99
• /
• 2007

This study has successfully demonstrated the direct fabrication of polymer resistors using ink-jet printing technology as an alternative patterning to traditional photolithography. The polymer resistors were fabricated just by two layer processes using a ink-jet printer (DMP-2800, Fujifilm Dimatix). First, resistive materials was patterned by a ink-jet printing with the desired width and length. Next, resistor fabrication was completed by printing metal contact pads on the both sides of the polymer resistor. We used poly (3,4-ethylene dioxythiophene) poly(styrenesulfonate)(PEDOT:PSS) for the resistor material and a nano-sized silver colloid for the metal contact pads. We characterized the electrical properties of PEDOT:PSS by measuring sheet resistance and specific resistance on a glass substrate. From analysis of the measured resistances, the electrical resistances of the polymer resistors linearly increased as a function of printed width and length of resistors. The accuracy of the fabricated polymer resistor showed about $0.6{\sim}2.5%$ error for the same dimensions.

• 한국전기전자재료학회논문지
• /
• 제26권3호
• /
• pp.171-176
• /
• 2013

In this paper, we present a MEMS (micro-electro-mechanical system) implantable blood pressure sensor which has designed and fabricated with consideration of size, design flexibility, and wireless detection. Mechanical and electrical characterizations of the sensor were obtained by mathematical analysis and computer aided simulation. The sensor is composed of two coils and a air gap capacitor formed by separation of the coils. Therefore, the sensor produces its resonant frequency which is changed by external pressure variation. This frequency movement is detected by inductive coupling between the sensor and an external antenna coil. Theoretically analyzed resonant frequency of the sensor under 760 mmHg was calculated to 269.556 MHz. Fused silica was selected as sensor material with consideration of chemical and electrical reaction of human body to the material. $2mm{\times}5mm{\times}0.5mm$ pressure sensors fitted to radial artery were fabricated on the substrates by consecutive microfabrication processes: sputtering, etching, photolithography, direct bonding and laser welding. Resonant frequencies of the fabricated sensors were in the range of 269~284 MHz under 760 mmHg pressure.

• 한국전기전자재료학회:학술대회논문집
• /
• 한국전기전자재료학회 2007년도 추계학술대회 논문집
• /
• pp.416-417
• /
• 2007

MmSH injection molding method to fabricate light guiding plate with nano-sized pattern was developed. A stamper was fabricated through photolithography, dry etching, and electroplating processes. While the stamper with nano-sized pattern in mold was kept at $180^{\circ}C$ during injection process, that was cooled down to $90^{\circ}C$ quickly after the injection process. The nano-sized pattern on light guiding plate processed by MmSH injection molding method was well transferred from stamper compared to that processed by conventional injection molding process.

• 열처리공학회지
• /
• 제31권2호
• /
• pp.63-67
• /
• 2018

Recent mold industry uses many roll-to-roll processes that can produce high production speed and precision machining and automation process. In the circular cylinder mold, however, patterns of less than $10{\mu}m$ are difficult to manufacture and maintain. In this study, we fabricated a circular cylindrical mold with a DLC thin film which have high hardness, low coefficient of friction and high releasability by using lithography and lift-off process. The height, line width, and pitch of the fabricated DLC macro pattern are $3.1{\mu}m$, $9.1{\mu}m$ and $20.2{\mu}m$, respectively. The pattern size is finer than the current applied to the aluminum cylinder type, and this shows the possibility of practical use of DLC micro pattern roll mold.

• Current Optics and Photonics
• /
• 제7권6호
• /
• pp.638-654
• /
• 2023

Holography is generally known as a technology that records and reconstructs 3D images by simultaneously capturing the intensity and phase information of light. Two or more interfering beams and illumination of this interference pattern onto a photosensitive recording medium allow us to control both the intensity and phase of light. Holography has found widespread applications not only in 3D imaging but also in manufacturing. In fact, it has been commonly used in semiconductor manufacturing, where interference light patterns are applied to photolithography, effectively reducing the half-pitch and period of line patterns, and enhancing the resolution of lithography. Moreover, holography can be used for the manufacturing of 3D regular structures (3D photonic crystals), not just surface patterns such as 1D or 2D gratings, and this can be broadly divided into (i) holographic recording and (ii) holographic lithography. In this review, we conceptually contrast two seemingly similar but fundamentally different manufacturing methods: holographic recording and holographic lithography. We comprehensively describe the differences in the manufacturing processes and the resulting structural features, as well as elucidate the distinctions in the diffractive optical properties that can be derived from them. Lastly, we aim to summarize the unique perspectives through which each method can appear distinct, with the intention of sharing information about this field with both experts and non-experts alike.

• 반도체디스플레이기술학회지
• /
• 제23권2호
• /
• pp.82-86
• /
• 2024

With the growing field and growing interest in transparent organic light-emitting diodes (TOLED) in the industry, various attempts are being made to improve the transmittance and performance of TOLED. TOLEDs are expected to be used in next-generation displays such as mixture reality (MR) displays, displayable windows, televisions, etc. This study presents a mesh TOLED with better transmittance and luminescence characteristics than existing TOLEDs through an in-situ vacuum deposition method that does not require additional processes such as photolithography and etching. In this study the mesh TOLED's cathode consists of Mg: Ag 1:9 electrode. Mesh patterns are interconnected with a 6 nm layer of interlayer. We approached transmittance improvement up to 30% at 555 nm at the cathode electrode with similar current injection character, also we improved lumination characteristics up to 23% at 7 V driving condition.

• 한국시뮬레이션학회논문지
• /
• 제26권4호
• /
• pp.43-49
• /
• 2017

우리나라의 반도체와 디스플레이 산업의 발전으로 해당 분야에 대한 인력 수급이 더욱 활발해지고 있다. 이에 따라 학부의 반도체 수업에서는 기존의 이론에 최신 기술 동향뿐만 아니라 현장 중심형 실무 인재 양성을 위해 반도체 제작 공정도 심도 있게 다루고 있다. 하지만, 반도체 공정은 클린룸 안에 설치된 장비들과 고가의 재료들이 필요하기 때문에 대규모로 진행되는 학부 교육에서 공정 실습이 제공되기는 어렵다. 이 한계를 극복하기 위해 실제 공정이나 공정 이론을 시각화한 동영상 등이 보조 자료로서 사용되고 있으나, 실습으로 대체할 교보재로서는 부족하다. 본 연구에서는 이론 중심의 학부 교육에 간접적인 반도체 공정 실습을 제공하기 위해 3차원 기반의 가상 클린룸을 구현하고, 반도체 공정에서 가장 많이 사용되는 노광 장비에 대한 시뮬레이터를 구현하여 사진 공정 베이에 설치하였다. 본 연구에서 구현하는 공정 시뮬레이터는 학부 교육에서 다루는 이론을 시각화하는데 중점을 두었으며, 포토 마스크와 실리콘 웨이퍼의 정렬과 노광 공정의 진행 따른 감광제의 국부적 변화를 시각화하였다. 개발된 시뮬레이터는 모바일 기기 등과 같은 저성능의 컴퓨팅 환경에서도 실행될 수 있도록 메모리 사용을 최소화하여 실용성을 극대화 하였다.