1
|
Heo SJ, Shin JH, Jun BO, Jang JE. Vacuum Tunneling Transistor with Nano Vacuum Chamber for Harsh Environments. ACS Nano 2023; 17:19696-19708. [PMID: 37803487 PMCID: PMC10604106 DOI: 10.1021/acsnano.3c02916] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/31/2023] [Accepted: 10/04/2023] [Indexed: 10/08/2023]
Abstract
A nano vacuum tube which consists of a vacuum transistor and a nano vacuum chamber was demonstrated. For the device, a vacuum region is an electron transport channel, and a vacuum is a tunneling barrier. Tilted angle evaporation was studied for the formation of the nano level vacuum chamber structure. This vacuum tube was ultraminiaturized with several tens of 10-18 L scale volume and 10-6 Torr of pressure. The device structure made it possible to achieve a high integration density and to sustain the vacuum state in various real operations. In particular, the vacuum transistor performed stably in extreme external environments because the tunneling mechanism showed a wide range of working stability. The vacuum was sustained well by the sealing layer and provided a defect-free tunneling junction. In tests, the high vacuum level was maintained for more than 15 months with high reliability. The Al sealing layer and tube structure can effectively block exposed light such as visible light and UV, enabling the stable operation of the tunneling transistor. In addition, it is estimated that the structure blocks approximately 5 keV of X-ray. The device showed stable operating characteristics in a wide temperature range of 100-390 K. Therefore, the vacuum tube can be used in a wide range of applications involving integrated circuits while resolving the disadvantages of a large volume in old vacuum tubes. Additionally, it can be an important solution for next-generation devices in various fields such as aerospace, artificial intelligence, and THz applications.
Collapse
Affiliation(s)
- Su Jin Heo
- Department
of Electrical Engineering and Computer Science (EECS), Daegu Gyeongbuk Institute of Science and Technology
(DGIST), Daegu 42988, Republic
of Korea
| | - Jeong Hee Shin
- Electronic
Convergence Materials Center, Korea Institute
of Ceramic Engineering and Technology (KICET), Jinju 52851, Republic of Korea
| | - Byoung Ok Jun
- Samsung
Electronics Foundry Business Department, Hwaseong 18448, Republic of Korea
| | - Jae Eun Jang
- Department
of Electrical Engineering and Computer Science (EECS), Daegu Gyeongbuk Institute of Science and Technology
(DGIST), Daegu 42988, Republic
of Korea
| |
Collapse
|
2
|
Kim J, Kim M, Jung H, Park J, Jun BO, Kang B, Jang JE, Lee Y. High-Quality Microprintable and Stretchable Conductors for High-Performance 5G Wireless Communication. ACS Appl Mater Interfaces 2022; 14:53250-53260. [PMID: 36382782 DOI: 10.1021/acsami.2c18424] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/16/2023]
Abstract
With the advent of 5G wireless and Internet of Things technologies, flexible and stretchable printed circuit boards (PCBs) should be designed to address all the specifications necessary to receive signal transmissions, maintaining the signal integrity, and providing electrical connections. Here, we propose a silver nanoparticle (AgNP)/silver nanowire (AgNW) hybrid conductor and high-quality microprinting technology for fabricating flexible and stretchable PCBs in high-performance 5G wireless communication. A simple and low-cost reverse offset printing technique using a commercial adhesive hand-roller was adapted to ensure high-resolution and excellent pattern quality. The AgNP/AgNW micropatterns were fabricated in various line widths, from 5 μm to 5 mm. They exhibited excellent pattern qualities, such as fine line spacing, clear edge definition and outstanding pattern uniformity. After annealing via intense pulsed light irradiation, they showed outstanding electrical resistivity (15.7 μΩ cm). Moreover, they could withstand stretching up to a strain of 90% with a small change in resistance. As a demonstration of their practical application, the AgNP/AgNW micropatterns were used to fabricate 5G communication antennas that exhibited excellent wireless signal processing at operating frequencies in the C-band (4-8 GHz). Finally, a wearable sensor fabricated with these AgNP/AgNW micropatterns could successfully detected fine finger movements in real time with excellent sensitivity.
Collapse
Affiliation(s)
- Jongyoun Kim
- Department of Energy Science and Engineering, Daegu Gyeongbuk Institute of Science and Technology (DGIST), 333 Techno Jungang-daero, Hyeonpung-Eup, Dalseong-Gun, Daegu 42988, Republic of Korea
| | - Minkyoung Kim
- Department of Energy Science and Engineering, Daegu Gyeongbuk Institute of Science and Technology (DGIST), 333 Techno Jungang-daero, Hyeonpung-Eup, Dalseong-Gun, Daegu 42988, Republic of Korea
| | - Hyeonwoo Jung
- Department of Energy Science and Engineering, Daegu Gyeongbuk Institute of Science and Technology (DGIST), 333 Techno Jungang-daero, Hyeonpung-Eup, Dalseong-Gun, Daegu 42988, Republic of Korea
| | - Jaehyoung Park
- Department of Energy Science and Engineering, Daegu Gyeongbuk Institute of Science and Technology (DGIST), 333 Techno Jungang-daero, Hyeonpung-Eup, Dalseong-Gun, Daegu 42988, Republic of Korea
| | - Byoung Ok Jun
- Department of Electrical Engineering & Computer Science, Daegu Gyeongbuk Institute of Science and Technology (DGIST), 333 Techno Jungang-daero, Hyeonpung-Eup, Dalseong-Gun, Daegu 42988, Republic of Korea
| | - Byeongjae Kang
- Department of Energy Science and Engineering, Daegu Gyeongbuk Institute of Science and Technology (DGIST), 333 Techno Jungang-daero, Hyeonpung-Eup, Dalseong-Gun, Daegu 42988, Republic of Korea
| | - Jae Eun Jang
- Department of Electrical Engineering & Computer Science, Daegu Gyeongbuk Institute of Science and Technology (DGIST), 333 Techno Jungang-daero, Hyeonpung-Eup, Dalseong-Gun, Daegu 42988, Republic of Korea
| | - Youngu Lee
- Department of Energy Science and Engineering, Daegu Gyeongbuk Institute of Science and Technology (DGIST), 333 Techno Jungang-daero, Hyeonpung-Eup, Dalseong-Gun, Daegu 42988, Republic of Korea
| |
Collapse
|
3
|
Jun BO, Kim H, Heo SJ, Kim J, Yang JH, Kim S, Kim K, Jin W, Choi J, Jang JE. Miniaturized Self-Resonant Micro Coil Array with A Floating Structure for Wireless Multi-Channel Transmission. Adv Sci (Weinh) 2021; 8:e2102944. [PMID: 34716695 PMCID: PMC8693062 DOI: 10.1002/advs.202102944] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/08/2021] [Revised: 08/16/2021] [Indexed: 06/13/2023]
Abstract
Micro size antennas have significant merits due to the small size effect, enabling new device concepts. However, the low-quality factor (Q-factor), the large size of impedance matching components, and the poor selectivity of the multi-array design remain challenging issues. To solve these issues, a floating coil structure stacked on a loop micro-antenna is suggested. Various floating coil designs are prepared with appropriate matching conditions at specific target frequencies, using an easy fabrication process without the need for additional space. A simple one-loop antenna design shows a higher Q-factor than other, more complicated designs. The micro-sized loop antenna with the 80 µm trace width design exhibits the highest Q-factor, around 31 within 7 GHz. The 8 different floating coil designs result in high-frequency selectivity from 1 to 7 GHz. The highest selectivity contrast and WPT efficiency are above 7 and around 1%, respectively. Considering the size of the antenna, the efficiency is not low, mainly due to the good matching effect with the high Q-factor of the floating coil and the loop antenna. This micro-antenna array concept with high integration density can be applied for advanced wireless neural stimulation or in wireless pixel array concepts in flexible displays.
Collapse
Affiliation(s)
- Byoung Ok Jun
- Department of Information and Communication EngineeringDaegu Gyeongbuk Institute of Science & Technology (DGIST)Daegu711–873Korea
| | - Han‐Joon Kim
- Department of Electrical and Computer EngineeringNational University of SingaporeSingapore119077Singapore
| | - Su Jin Heo
- Department of Information and Communication EngineeringDaegu Gyeongbuk Institute of Science & Technology (DGIST)Daegu711–873Korea
| | - Jonghyeun Kim
- Department of Information and Communication EngineeringDaegu Gyeongbuk Institute of Science & Technology (DGIST)Daegu711–873Korea
| | - Jae Hoon Yang
- Department of Information and Communication EngineeringDaegu Gyeongbuk Institute of Science & Technology (DGIST)Daegu711–873Korea
| | - Seunguk Kim
- Department of Information and Communication EngineeringDaegu Gyeongbuk Institute of Science & Technology (DGIST)Daegu711–873Korea
| | - Kyungtae Kim
- Department of Information and Communication EngineeringDaegu Gyeongbuk Institute of Science & Technology (DGIST)Daegu711–873Korea
| | - Woo‐Cheol Jin
- Department of Information and Communication EngineeringDaegu Gyeongbuk Institute of Science & Technology (DGIST)Daegu711–873Korea
| | - Ji‐Woong Choi
- Department of Information and Communication EngineeringDaegu Gyeongbuk Institute of Science & Technology (DGIST)Daegu711–873Korea
| | - Jae Eun Jang
- Department of Information and Communication EngineeringDaegu Gyeongbuk Institute of Science & Technology (DGIST)Daegu711–873Korea
| |
Collapse
|
4
|
Lee GJ, Heo SJ, Lee S, Yang JH, Jun BO, Kim HS, Jang JE. Stress Release Effect of Micro-hole Arrays for Flexible Electrodes and Thin Film Transistors. ACS Appl Mater Interfaces 2020; 12:19226-19234. [PMID: 32237721 DOI: 10.1021/acsami.0c02362] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
The effects of micro-hole arrays in the thin metal films were studied as a method to release bending stress in flexible electrodes and flexible thin film transistors (TFTs). Interest in flexible electronics is increasing, and many approaches have been suggested to solve the issue of the electrical failure of electrodes or electrical components such as TFTs after repeated bending. Here, we demonstrate a micro-hole array structure as a common solution to release bending stress. Although micro-size cracks were generated and propagated from the hole edges, the cracks stopped within a certain range when enough stress was released. Moreover, since the crack sites were predictable and controllable, a fatal electrical breakdown in a conductive layer such as a metal electrode or the semiconducting junction of a TFT can be prevented by specifically arranging the hole arrays. Thin film layers fabricated without holes suffered an electrical breakdown due to random crack propagation during bending tests. Aluminum thin film electrodes prepared with arrays of 3 μm diameter holes and 25% hole area showed excellent durability after 300,000 bending cycles. The change in resistance was below 3%. The electrical characteristics of an a-IGZO TFT with the micro-hole structure were almost equivalent to a standard a-IGZO TFT. After 10,000 bending cycles, ION and the ratio of ION/IOFF remained >107 A and ∼107, respectively. Since the effective hole diameter is micrometer in size, fabrication does not require additional process steps or expensive process equipment. Therefore, the approach can be an important way to enhance the reliability of various electrical devices in flexible and wearable applications.
Collapse
Affiliation(s)
- Gwang Jun Lee
- Department of Information and Communication Engineering, Daegu Gyeongbuk Institute of Science and Technology (DGIST), Daegu 42988, Republic of Korea
| | - Su Jin Heo
- Department of Information and Communication Engineering, Daegu Gyeongbuk Institute of Science and Technology (DGIST), Daegu 42988, Republic of Korea
| | - Seungchul Lee
- Department of Information and Communication Engineering, Daegu Gyeongbuk Institute of Science and Technology (DGIST), Daegu 42988, Republic of Korea
- Samsung Electronics, Hwaseong 18448, Republic of Korea
| | - Jae Hoon Yang
- Department of Information and Communication Engineering, Daegu Gyeongbuk Institute of Science and Technology (DGIST), Daegu 42988, Republic of Korea
| | - Byoung Ok Jun
- Department of Information and Communication Engineering, Daegu Gyeongbuk Institute of Science and Technology (DGIST), Daegu 42988, Republic of Korea
| | - Hyun Sik Kim
- Department of Materials Science and Engineering, Hongik University, Seoul 04066, Republic of Korea
| | - Jae Eun Jang
- Department of Information and Communication Engineering, Daegu Gyeongbuk Institute of Science and Technology (DGIST), Daegu 42988, Republic of Korea
| |
Collapse
|
5
|
Abstract
Geometric effects of nano-hole arrays were investigated for label free bio-detection.
Collapse
Affiliation(s)
- Seunguk Kim
- Department of Information and Communication Engineering
- Daegu Gyeongbuk Institute of Science and Technology (DGIST)
- Daegu
- Korea
| | - Jeong Hee Shin
- Department of Information and Communication Engineering
- Daegu Gyeongbuk Institute of Science and Technology (DGIST)
- Daegu
- Korea
| | - Samhwan Kim
- Department of Brain & Cognitive Sciences
- Daegu Gyeongbuk Institute of Science and Technology (DGIST)
- Daegu
- Korea
| | - Seung-Jun Yoo
- Department of Brain & Cognitive Sciences
- Daegu Gyeongbuk Institute of Science and Technology (DGIST)
- Daegu
- Korea
| | - Byoung Ok Jun
- Department of Information and Communication Engineering
- Daegu Gyeongbuk Institute of Science and Technology (DGIST)
- Daegu
- Korea
| | - Cheil Moon
- Department of Brain & Cognitive Sciences
- Daegu Gyeongbuk Institute of Science and Technology (DGIST)
- Daegu
- Korea
| | - Jae Eun Jang
- Department of Information and Communication Engineering
- Daegu Gyeongbuk Institute of Science and Technology (DGIST)
- Daegu
- Korea
| |
Collapse
|
6
|
Jun BO, Lee GJ, Kang JG, Kim S, Choi JW, Cha SN, Sohn JI, Jang JE. Wireless thin film transistor based on micro magnetic induction coupling antenna. Sci Rep 2015; 5:18621. [PMID: 26691929 PMCID: PMC4686891 DOI: 10.1038/srep18621] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2015] [Accepted: 11/20/2015] [Indexed: 11/09/2022] Open
Abstract
A wireless thin film transistor (TFT) structure in which a source/drain or a gate is connected directly to a micro antenna to receive or transmit signals or power can be an important building block, acting as an electrical switch, a rectifier or an amplifier, for various electronics as well as microelectronics, since it allows simple connection with other devices, unlike conventional wire connections. An amorphous indium gallium zinc oxide (α-IGZO) TFT with magnetic antenna structure was fabricated and studied for this purpose. To enhance the induction coupling efficiency while maintaining the same small antenna size, a magnetic core structure consisting of Ni and nanowires was formed under the antenna. With the micro-antenna connected to a source/drain or a gate of the TFT, working electrical signals were well controlled. The results demonstrated the device as an alternative solution to existing wire connections which cause a number of problems in various fields such as flexible/wearable devices, body implanted devices, micro/nano robots, and sensors for the 'internet of things' (IoT).
Collapse
Affiliation(s)
- Byoung Ok Jun
- Daegu Gyeongbuk Institute of Science and Technology (DGIST), Department of Information and Communication Engineering, Daegu, 711-873, Korea
| | - Gwang Jun Lee
- Daegu Gyeongbuk Institute of Science and Technology (DGIST), Department of Information and Communication Engineering, Daegu, 711-873, Korea
| | - Jong Gu Kang
- Daegu Gyeongbuk Institute of Science and Technology (DGIST), Department of Information and Communication Engineering, Daegu, 711-873, Korea.,Advanced Naval Technology Center, Agency for Defense Development, Changwon, 645-600, Korea
| | - Seunguk Kim
- Daegu Gyeongbuk Institute of Science and Technology (DGIST), Department of Information and Communication Engineering, Daegu, 711-873, Korea
| | - Ji-Woong Choi
- Daegu Gyeongbuk Institute of Science and Technology (DGIST), Department of Information and Communication Engineering, Daegu, 711-873, Korea
| | - Seung Nam Cha
- University of Oxford, Department of Electrical Engineering Science, Oxford, OXI 3PJ, U. K
| | - Jung Inn Sohn
- University of Oxford, Department of Electrical Engineering Science, Oxford, OXI 3PJ, U. K
| | - Jae Eun Jang
- Daegu Gyeongbuk Institute of Science and Technology (DGIST), Department of Information and Communication Engineering, Daegu, 711-873, Korea
| |
Collapse
|
7
|
Lee Y, Jun BO, Kim SG, Kwon YM. Purification of ornithine carbamoyltransferase from kidney bean (Phaseolus vulgaris L.) leaves and comparison of the properties of the enzyme from canavanine-containing and -deficient plants. Planta 1998; 205:375-379. [PMID: 9640663 DOI: 10.1007/s004250050333] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
Kidney bean (Phaseolus vulgaris L.) ornithine carbamoyltransferase (OCT; EC 2.1.3.3) was purified to homogeneity from leaf homogenates in a single-step procedure, using delta-N-(phosphonoacetyl)-L-ornithine-Sepharose 6B affinity chromatography. The 8540-fold-purified OCT exhibited a specific activity of 526 micromoles citrulline per minute per milligram of protein at 35 degrees C and pH 8.0. The enzyme represents approximately 0.01% of the total soluble protein in the leaf. The molecular mass of the native enzyme was approximately 109 kDa as estimated by Sephacryl S-200 gel filtration chromatography. The purified protein ran as a single band of molecular mass 36 kDa when subjected to sodium dodecyl sulfate-polyacrylamide gel electrophoresis and at a single isoelectric point of 6.6 when subjected to denaturing isoelectric focusing. These results suggest that the enzyme is a trimer of identical subunits. Among the tested amino acids, L-cysteine and S-carbamoyl-L-cysteine were the most effective inhibitors of the enzyme. The OCT of kidney bean showed a very low activity towards canaline. The OCTs of canavanine-deficient plants have very low canaline-dependent activities, but the OCTs of canavanine-containing plants showed high canaline-dependent activities. It was assumed that the substrate specificity of this enzyme determines the canavanine synthetic activity of the urea cycle.
Collapse
Affiliation(s)
- Y Lee
- Department of Biology, Seoul National University, Korea
| | | | | | | |
Collapse
|