The Experts below are selected from a list of 6567 Experts worldwide ranked by ideXlab platform
Jong-wan Park - One of the best experts on this subject based on the ideXlab platform.
-
improvement in device performance of a ingazno transistors by introduction of ca doped cu source Drain Electrode
IEEE Electron Device Letters, 2015Co-Authors: Sangho Lee, Jae Kyeong Jeong, Ah Young Hwang, Dongsuk Han, Shin Kim, Jong-wan ParkAbstract:This letter reports the effects of Ca doping into Cu films, which was used as a source/Drain (S/D) Electrode for high performance amorphous In–Ga–Zn–O (IGZO) thin-film transistors (TFTs) with a low resistive–capacitive delay time. The IGZO TFTs with Ca-doped Cu S/D exhibited three times higher saturation mobility (16 cm $^{2}$ /Vs) and substantially lower subthreshold gate swing of 0.39 V/decade than the control devices with pure Cu S/D. The SIMS profile and cross-sectional transmission electron microscopy showed that Ca effectively prevented the Cu atoms from diffusing into channel IGZO region presumably as a result of Ca–O bond formation, which is responsible for their superior device performances.
-
influence of molybdenum source Drain Electrode contact resistance in amorphous zinc tin oxide a zto thin film transistors
Materials Research Bulletin, 2014Co-Authors: Dongsuk Han, Yu-jin Kang, Jae-hyung Park, Hyung-tag Jeon, Jong-wan ParkAbstract:Highlights: • We developed and investigated source/Drain Electrodes in oxide TFTs. • The Mo S/D Electrodes showed good output characteristics. • Intrinsic TFT parameters were calculated by the transmission line method. - Abstract: This paper investigates the feasibility of a low-resistivity Electrode material (Mo) for source/Drain (S/D) Electrodes in thin film transistors (TFTs). The effective resistances between Mo source/Drain Electrodes and amorphous zinc–tin-oxide (a-ZTO) thin film transistors were studied. Intrinsic TFT parameters were calculated by the transmission line method (TLM) using a series of TFTs with different channel lengths measured at a low source/Drain voltage. The TFTs fabricated with Mo source/Drain Electrodes showed good transfer characteristics with a field-effect mobility of 10.23 cm{sup 2}/V s. In spite of slight current crowding effects, the Mo source/Drain Electrodes showed good output characteristics with a steep rise in the low Drain-to-source voltage (V{sub DS}) region.
-
Influence of molybdenum source/Drain Electrode contact resistance in amorphous zinc–tin-oxide (a-ZTO) thin film transistors
Materials Research Bulletin, 2014Co-Authors: Dongsuk Han, Yu-jin Kang, Jae-hyung Park, Hyung-tag Jeon, Jong-wan ParkAbstract:Highlights: • We developed and investigated source/Drain Electrodes in oxide TFTs. • The Mo S/D Electrodes showed good output characteristics. • Intrinsic TFT parameters were calculated by the transmission line method. - Abstract: This paper investigates the feasibility of a low-resistivity Electrode material (Mo) for source/Drain (S/D) Electrodes in thin film transistors (TFTs). The effective resistances between Mo source/Drain Electrodes and amorphous zinc–tin-oxide (a-ZTO) thin film transistors were studied. Intrinsic TFT parameters were calculated by the transmission line method (TLM) using a series of TFTs with different channel lengths measured at a low source/Drain voltage. The TFTs fabricated with Mo source/Drain Electrodes showed good transfer characteristics with a field-effect mobility of 10.23 cm{sup 2}/V s. In spite of slight current crowding effects, the Mo source/Drain Electrodes showed good output characteristics with a steep rise in the low Drain-to-source voltage (V{sub DS}) region.
-
copper source Drain Electrode contact resistance effects in amorphous indium gallium zinc oxide thin film transistors
Physica Status Solidi-rapid Research Letters, 2009Co-Authors: Woong-sun Kim, Yeon-keon Moon, Sih Lee, Byung-woo Kang, Tae-seok Kwon, Kyung-taek Kim, Jong-wan ParkAbstract:This paper focuses on the viability of low-resistivity Electrode material (Cu) for source/Drain Electrodes in thin film transistors (TFTs). The effective resistances between Cu source/Drain Electrodes and amorphous indium gallium zinc oxide (a-IGZO) thin-film transistors were examined. Intrinsic TFT parameters were extracted by the transmission line method (TLM) using a series of TFTs with different channel lengths measured at a low source/Drain voltage. The TFTs fabricated with Cu source/Drain Electrodes showed good transfer characteristics with a field-effect mobility of 9.64 cm2/Vs, and good output characteristics with steep rise in the low VDS region. (© 2009 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)
-
Copper source/Drain Electrode contact resistance effects in amorphous indium–gallium–zinc-oxide thin film transistors
physica status solidi (RRL) - Rapid Research Letters, 2009Co-Authors: Woong-sun Kim, Yeon-keon Moon, Sih Lee, Byung-woo Kang, Tae-seok Kwon, Kyung-taek Kim, Jong-wan ParkAbstract:This paper focuses on the viability of low-resistivity Electrode material (Cu) for source/Drain Electrodes in thin film transistors (TFTs). The effective resistances between Cu source/Drain Electrodes and amorphous indium gallium zinc oxide (a-IGZO) thin-film transistors were examined. Intrinsic TFT parameters were extracted by the transmission line method (TLM) using a series of TFTs with different channel lengths measured at a low source/Drain voltage. The TFTs fabricated with Cu source/Drain Electrodes showed good transfer characteristics with a field-effect mobility of 9.64 cm2/Vs, and good output characteristics with steep rise in the low VDS region. (© 2009 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)
Jae Kyeong Jeong - One of the best experts on this subject based on the ideXlab platform.
-
high performance metal oxide field effect transistors with a reverse offset printed cu source Drain Electrode
ACS Applied Materials & Interfaces, 2016Co-Authors: Young Hun Han, Ju Yeon Won, Hyun Seok Yoo, Jae Hyun Kim, Rino Choi, Jae Kyeong JeongAbstract:Nonvacuum and photolithography-free copper (Cu) films were prepared by reverse offset printing. The mechanical, morphological, structural, and chemical properties of the Cu films annealed at different temperatures were examined in detail. The Ostwald ripening-induced coalescence and grain growth in the printing Cu films were enhanced with increasing annealing temperature in N2 ambient up to 400 °C. Simultaneously, unwanted chemical impurities such as oxygen, hydrogen, and carbon in the Cu films decreased as the annealing temperature increased. The high electrical conductivity (∼6.2 μΩ·cm) of the printing Cu films annealed at 400 °C is attributed to the enlargement of the grain size and reduction of the incorporation of impurities. A printing Cu film was adopted as a source/Drain (S/D) Electrode in solution processable zinc tin oxide (ZTO) field-effect transistors (FETs), where the ZTO film was prepared by simple spin-coating. The ZTO FETs fabricated at a contact annealing temperature of 250 °C exhibited a...
-
improvement in device performance of a ingazno transistors by introduction of ca doped cu source Drain Electrode
IEEE Electron Device Letters, 2015Co-Authors: Sangho Lee, Jae Kyeong Jeong, Ah Young Hwang, Dongsuk Han, Shin Kim, Jong-wan ParkAbstract:This letter reports the effects of Ca doping into Cu films, which was used as a source/Drain (S/D) Electrode for high performance amorphous In–Ga–Zn–O (IGZO) thin-film transistors (TFTs) with a low resistive–capacitive delay time. The IGZO TFTs with Ca-doped Cu S/D exhibited three times higher saturation mobility (16 cm $^{2}$ /Vs) and substantially lower subthreshold gate swing of 0.39 V/decade than the control devices with pure Cu S/D. The SIMS profile and cross-sectional transmission electron microscopy showed that Ca effectively prevented the Cu atoms from diffusing into channel IGZO region presumably as a result of Ca–O bond formation, which is responsible for their superior device performances.
-
high performance zn sn o thin film transistors with cu source Drain Electrode
Physica Status Solidi-rapid Research Letters, 2013Co-Authors: Chul Kyu Lee, Hong Yoon Jung, Chang Kyu Lee, Byeong Geun Son, Hyo Jin Kim, Young-joo Lee, Young-chang Joo, Se Yeob Park, Jae Kyeong JeongAbstract:Zn–Sn–O (ZTO) thin film transistors (TFTs) were fabricated with a Cu source/Drain Electrode. Although a reasonably high mobility (μFE) of 13.2 cm2/Vs was obtained for the ZTO TFTs, the subthreshold gate swing (SS) and threshold voltage (Vth) of 1.1 V/decade and 9.1 V, respectively, were inferior. However, ZTO TFTs with Ta film inserted as a diffusion barrier, exhibited improved SS and Vth values of 0.48 V/decade and 3.0 V, respectively as well as a high μFE value of 18.7 cm2/Vs. The improvement in the Ta-inserted device was attributed to the suppression of Cu lateral diffusion into the ZTO channel region. (© 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)
-
High performance Zn–Sn–O thin film transistors with Cu source/Drain Electrode
physica status solidi (RRL) - Rapid Research Letters, 2013Co-Authors: Chul Kyu Lee, Yeob Park, Hong Yoon Jung, Chang Kyu Lee, Byeong Geun Son, Hyo Jin Kim, Young-joo Lee, Young-chang Joo, Jae Kyeong JeongAbstract:Zn–Sn–O (ZTO) thin film transistors (TFTs) were fabricated with a Cu source/Drain Electrode. Although a reasonably high mobility (μFE) of 13.2 cm2/Vs was obtained for the ZTO TFTs, the subthreshold gate swing (SS) and threshold voltage (Vth) of 1.1 V/decade and 9.1 V, respectively, were inferior. However, ZTO TFTs with Ta film inserted as a diffusion barrier, exhibited improved SS and Vth values of 0.48 V/decade and 3.0 V, respectively as well as a high μFE value of 18.7 cm2/Vs. The improvement in the Ta-inserted device was attributed to the suppression of Cu lateral diffusion into the ZTO channel region. (© 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)
-
improvements in the device characteristics of amorphous indium gallium zinc oxide thin film transistors by ar plasma treatment
Applied Physics Letters, 2007Co-Authors: Jinseong Park, Jae Kyeong Jeong, Hyedong Kim, Sunil KimAbstract:The effect of Ar plasma treatment on amorphous indium gallium zinc oxide (a-IGZO) thin films was investigated. The net electron carrier concentration (1020–1021cm−3) of the a-IGZO thin films dramatically increased upon their exposure to the Ar plasma compared to that (1014cm−3) of the as-deposited thin film. The authors attempted to reduce the contact resistance between the Pt∕Ti (source/Drain Electrode) and a-IGZO (channel) by using the Ar plasma treatment. Without the treatment, the a-IGZO thin film transistors (TFTs) with W∕L=50∕4μm exhibited a moderate field-effect mobility (μFE) of 3.3cm2∕Vs, subthreshold gate swing (S) of 0.25V∕decade, and Ion∕off ratio of 4×107. The device performance of the a-IGZO TFTs was significantly improved by the Ar plasma treatment. As a result, an excellent S value of 0.19V∕decade and high Ion∕off ratio of 1×108, as well as a high μFE of 9.1cm2∕Vs, were achieved for the treated a-IGZO TFTs.
Shi-woo Rhee - One of the best experts on this subject based on the ideXlab platform.
-
plasma damage on the ots treated sio2 substrate in the source Drain Electrode deposition process
Journal of The Electrochemical Society, 2010Co-Authors: Dong-jin Yun, Shi-woo RheeAbstract:Pentacene thin film transistors (TFTs) were made using different deposition tools and patterning methods to confirm the degradation of the octadecyltrichlorosilane (OTS) monolayer due to plasma damage during sputter deposition or to thermal damage during the evaporation deposition process. The degradation of the OTS monolayer was confirmed by studying the morphology of pentacene grown on the OTS monolayer and the electrical properties of pentacene TFTs. The OTS monolayer on Si0 2 /N + +Si substrate was not degraded by thermal energy during evaporation, but it was affected by plasma damage during sputtering. Pentacene grown on the OTS monolayer did not show well-defined grains when the OTS monolayer was exposed to plasma, and the performance improvement in the pentacene TFT was not observed. In the lift-off method, the OTS monolayer was covered with photoresist, which could prevent sputtering damage, and OTS treatment improved the performance of the pentacene TFT.
-
deposition of al doped zno thin films with radio frequency magnetron sputtering for a source Drain Electrode for pentacene thin film transistor
Thin Solid Films, 2009Co-Authors: Dong-jin Yun, Shi-woo RheeAbstract:Abstract Al-doped ZnO thin-films were deposited with the radio frequency magnetron sputtering technique at various temperatures and sputtering powers for a source/Drain Electrode in the pentacene thin-film transistor. With the increase in the deposition temperature and the decrease in the radio frequency sputtering power, the crystallinity was increased and the surface roughness was decreased, which lead to the decrease in the electrical resistivity of the film. Al-doped ZnO film deposited at 200 °C and sputtering power of 50 W showed a low resistivity (9.73 × 10 4 μΩcm), high crystallinity, low roughness and uniform surface morphology. The pentacene thin-film transistor fabricated with Al-doped ZnO film as a source/Drain Electrode showed a device performance, (mobility: 7.89 × 10 − 3 cm 2 /Vs and on/off ratio: ~ 5 × 10 4 ) which is comparable with an indium tin oxide Electrode grown at room temperature.
-
Deposition of Al-doped ZnO thin-films with radio frequency magnetron sputtering for a source/Drain Electrode for pentacene thin-film transistor
Thin Solid Films, 2009Co-Authors: Dong-jin Yun, Shi-woo RheeAbstract:Abstract Al-doped ZnO thin-films were deposited with the radio frequency magnetron sputtering technique at various temperatures and sputtering powers for a source/Drain Electrode in the pentacene thin-film transistor. With the increase in the deposition temperature and the decrease in the radio frequency sputtering power, the crystallinity was increased and the surface roughness was decreased, which lead to the decrease in the electrical resistivity of the film. Al-doped ZnO film deposited at 200 °C and sputtering power of 50 W showed a low resistivity (9.73 × 10 4 μΩcm), high crystallinity, low roughness and uniform surface morphology. The pentacene thin-film transistor fabricated with Al-doped ZnO film as a source/Drain Electrode showed a device performance, (mobility: 7.89 × 10 − 3 cm 2 /Vs and on/off ratio: ~ 5 × 10 4 ) which is comparable with an indium tin oxide Electrode grown at room temperature.
-
pentacene thin film transistor with nio x as a source Drain Electrode deposited with sputtering
Journal of The Electrochemical Society, 2008Co-Authors: Dong-jin Yun, Shi-woo RheeAbstract:1,2 But the source‐Drain S/D contacts in OTFTs are not easily optimized by conventional processes, such as semiconductor doping or metal alloying. Interface properties between the S/D Electrode and semiconductor are critical factors for TFT performance. To reduce the hole injection barrier from the difference in the work function of the S/D Electrode and the highest occupied molecular orbital HOMO level of the semiconductor, it is important to choose a S/D Electrode which has a work function close to the HOMO level of the organic semiconductor. As a contact metal, gold Au, silver, calcium, and indium tin oxide were studied. 2-5 Until now, Au has been the most widely used S/D Electrode in pentacene TFT because it has a work function of 5.0 eV, which is close to the HOMO level of pentacene, 5.2 eV. Au may not be preferred in a real application, because as a noble metal, it is expensive and difficult to etch for patterning. Recently, it has been reported that high-performance pentacene TFTs could be made with NiOx S/D Electrode deposited using a thermal evaporator. 6-8 Up to now, there has been no information on the properties of NiOx film properties as a function of the film composition x as a S/D Electrode. It is easier to control the film composition with sputtering by controlling the oxygen flow rate than by thermal evaporation. In this study, radio frequency rf sputtering was used to obtain the nickeloxide film starting from the nickel-metal Ni metal target, and the effect of the composition on the performance of the pentacene TFTs was studied. The film composition was controlled with sputtering by varying the O2/Ar flow ratio. Film properties such as resistivity, fraction of the oxidation states of Ni 0, +2, +3, and the work function were measured. Also, pentacene TFTs using NiOx as S/D Electrodes were made, and their performance was compared with an Au/Ti Electrode. In our experiment, it is not easy to optimize all the processes and the materials involved in the TFT manufacturing, so the device performance cannot directly be compared with other research results with the highest mobility. We made the same TFT with gold and compared the performance. Gold is the most widely used metal, and the comparison can give a clear idea about the NiOx material.
In U Chung - One of the best experts on this subject based on the ideXlab platform.
-
fully transparent ingazno thin film transistors using indium tin oxide graphene multilayer as source Drain Electrodes
Applied Physics Letters, 2010Co-Authors: David Seo, Sanghun Jeon, Sunae Seo, Ihun Song, Changjung Kim, Sungho Park, J S Harris, In U ChungAbstract:Demonstration of a transparent InGaZnO thin film transistor using a graphene composite as the transparent source/Drain Electrode is presented. Graphene growth was confirmed by Raman spectroscopy, showing all associated peaks at 1350, 1580, and 2700 cm−1. The graphene composite showed a sheet resistance reduction of 15% while losing only 1.2% transparency when compared to the reference indium-tin oxide only Electrode. Device characteristics of the composite device were on similar levels to those of the reference indium-tin oxide only device reaching a peak saturation mobility of nearly 30 cm2 v−1 s−1 indicating that graphene integration did not degrade InGaZnO transistor performance.
Zhi-lin Zhang - One of the best experts on this subject based on the ideXlab platform.
-
feasibility of zno al ag zno al multilayer source Drain Electrode to achieve fully transparent hfinzno thin film transistor
Thin Solid Films, 2016Co-Authors: Jianhua Zhang, Xue-yin Jiang, Zhi-lin ZhangAbstract:Abstract We fabricated fully transparent hafnium indium zinc oxide (HfInZnO) thin film transistors (TFTs) with ZnO:Al(AZO)/Ag/ZnO:Al multilayer source/Drain (S/D) Electrodes. The effect of Ag interlayer thickness on the electrical and optical properties of AZO(60 nm)/Ag/AZO(60 nm) multilayer films was investigated. The AZO(60 nm)/Ag(10 nm)/AZO(60 nm) multilayer film shows a low sheet resistance of 10.5 Ω/square and a transmittance of 87%. Compared with HfInZnO-TFT with AZO Electrode, the performance of the device with AZO/Ag/AZO multilayer Electrode was significantly improved. The field effect mobility increased from 3.2 to 5.8 cm 2 /V s, and the threshold voltage reduced from 2.3 to 0.1 V. The improvement was attributed to the lower resistivity of AZO/Ag/AZO multilayer film. The result indicates that AZO/Ag/AZO multilayer Electrode is a promising S/D Electrode for fully transparent HfInZnO-TFTs.
-
reduction of the contact resistance in copper phthalocyanine thin film transistor with uv ozone treated au Electrodes
Current Applied Physics, 2010Co-Authors: Jun Li, Xiao-wen Zhang, Liang Zhang, Hao Zhang, Xue-yin Jiang, Dongbin Yu, Zhi-lin ZhangAbstract:Abstract Bottom-contact (BC) copper phthalocyanine (CuPc) thin film transistor with UV/ozone treated Au as a source/Drain Electrode was fabricated and the contact resistance was estimated from the transmission line method (TLM). Comparing the properties of OTFT with untreated Au Electrode, the performance of the BC CuPc-TFT with the UV/ozone treated Au Electrodes was significantly improved: saturation mobility increased from 4.69 × 10−3 to 2.37 × 10−2 cm2/V s, threshold voltage reduced from −29.1 to −6.4 V, and threshold swing varied from 5.08 to 2.25 V/decade. The contact resistance of the device with UV/ozone treated Au Electrodes was nearly 20 times smaller than that of the device with untreated Au Electrodes at the gate voltage of −20 V. This result indicated that using the UV/ozone treated Au Electrode is an effective method to reduce the contact resistance. The present BC configuration with UV/ozone treated Au Electrodes could be a significant step towards the commercialization of OTFT technology.
-
effect of a sinx insulator on device properties of pentacene tfts with a low cost copper source Drain Electrode
Semiconductor Science and Technology, 2010Co-Authors: Xiao-wen Zhang, Liang Zhang, Hao Zhang, Xue-yin Jiang, Wenqing Zhu, Zhi-lin ZhangAbstract:We fabricated different SiNx insulators at a 150–350 °C deposition temperature by plasma-enhanced chemical vapor deposition (PECVD) and investigated the effect of SiNx insulator on the device properties of pentacene-TFTs with a low-cost copper source/Drain Electrode. A pentacene-TFT with a SiNx insulator at a deposition temperature of 300 °C exhibited the highest saturation mobility of 0.29 cm2 (V s)−1, the lowest threshold voltage of −8.9 V and an on/off current ratio of 5.3 × 106. The best performance of the device with a SiNx insulator at a 300 °C deposition temperature can be attributed to the electrical properties and a relatively large water contact angle of insulator, smooth insulator surface and better crystallinity of the pentacene active layer. The present organic thin-film transistors (OTFTs) with the PECVD SiNx insulator and the low-cost Cu Electrode could be a significant step toward the commercialization of OTFT technology.
-
Effect of a SiNx insulator on device properties of pentacene-TFTs with a low-cost copper source/Drain Electrode
Semiconductor Science and Technology, 2010Co-Authors: Xiao-wen Zhang, Liang Zhang, Hao Zhang, Xue-yin Jiang, Wenqing Zhu, Zhi-lin ZhangAbstract:We fabricated different SiNx insulators at a 150–350 °C deposition temperature by plasma-enhanced chemical vapor deposition (PECVD) and investigated the effect of SiNx insulator on the device properties of pentacene-TFTs with a low-cost copper source/Drain Electrode. A pentacene-TFT with a SiNx insulator at a deposition temperature of 300 °C exhibited the highest saturation mobility of 0.29 cm2 (V s)−1, the lowest threshold voltage of −8.9 V and an on/off current ratio of 5.3 × 106. The best performance of the device with a SiNx insulator at a 300 °C deposition temperature can be attributed to the electrical properties and a relatively large water contact angle of insulator, smooth insulator surface and better crystallinity of the pentacene active layer. The present organic thin-film transistors (OTFTs) with the PECVD SiNx insulator and the low-cost Cu Electrode could be a significant step toward the commercialization of OTFT technology.