{"title":"Improved mobility in InAs nanowire FETs with sulfur-based surface treatment","authors":"Yen Hsueh Wu , Hong Hyuk Kim , Jae Cheol Shin","doi":"10.1016/j.cap.2024.11.015","DOIUrl":"10.1016/j.cap.2024.11.015","url":null,"abstract":"<div><div>InAs exhibits high electron mobility, positioning it as a promising candidate for advanced nanoelectronic device materials. Specifically, nanowire structures are particularly advantageous for electronic device applications, offering benefits such as reduced leakage current and minimized short-channel effects due to their distinctive one-dimensional electron transport characteristics. However, the large surface-to-volume ratio of the nanowires not only significantly degrades their electrical properties but also complicates the formation of semiconductor-metal ohmic contacts. In this study, surface treatments involving sulfur and (NH<sub>4</sub>)<sub>2</sub>S, along with rapid thermal annealing (RTA) processes, were applied to mitigate these disadvantages, resulting in a marked enhancement of the electrical properties of InAs nanowires. The electron mobility of the InAs nanowires was elevated from 83.06 cm<sup>2</sup>/V·s to 292.718 cm<sup>2</sup>/V·s through the application of passivation and RTA processes.</div></div>","PeriodicalId":11037,"journal":{"name":"Current Applied Physics","volume":"70 ","pages":"Pages 81-86"},"PeriodicalIF":2.4,"publicationDate":"2024-11-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142747435","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Graphene/WS2/LaVO3 heterojunction for self-powered, high-speed, and broadband photodetectors","authors":"Dong Hee Shin , Hosun Lee","doi":"10.1016/j.cap.2024.11.014","DOIUrl":"10.1016/j.cap.2024.11.014","url":null,"abstract":"<div><div>Recently, there has been interest in developing high-performance self-driven photodetectors (PDs) using 2D-based heterostructures due to their unique optoelectronic properties. Here, we demonstrate that vertical-heterostructures based on graphene (Gr) transparent conductive electrodes, n-type 2D WS<sub>2</sub>, and p-type LaVO<sub>3</sub> realize a broadband-responsive PD covering the wavelength range of 300–850 nm. Due to the formation of an electric field at the WS<sub>2</sub>/LaVO<sub>3</sub> interface and the photovoltaic effect, this structure shows a rectifying operation with a maximum detectivity of 2.1 × 10<sup>10</sup> Jones at zero bias. Additionally, it exhibits a fast fall time of 435 μs and a 3 dB bandwidth of 2300 Hz, making it suitable for high-speed self-powered optoelectronic applications. Therefore, the TETA-Gr/WS<sub>2</sub>/LaVO<sub>3</sub> heterojunction is proposed as an excellent candidate for high-performance, self-powered, and broadband PDs.</div></div>","PeriodicalId":11037,"journal":{"name":"Current Applied Physics","volume":"70 ","pages":"Pages 69-75"},"PeriodicalIF":2.4,"publicationDate":"2024-11-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142720527","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Takmo Jeong , Jiyoon Kim , Un Jeong Kim , Hyunjin Ji , Seok Joon Yun
{"title":"Oxidation effects on the optical and electrical properties of MoS2 under controlled baking temperatures","authors":"Takmo Jeong , Jiyoon Kim , Un Jeong Kim , Hyunjin Ji , Seok Joon Yun","doi":"10.1016/j.cap.2024.11.013","DOIUrl":"10.1016/j.cap.2024.11.013","url":null,"abstract":"<div><div>As silicon-based semiconductor technology scales down to the nanoscale, it encounters significant physical limitations, including reduced electron mobility, short-channel effects, and increased heat generation, which hinder device performance and reliability. Two-dimensional (2D) semiconductors, such as molybdenum disulfide (MoS<sub>2</sub>), offer great potential with superior electrical properties at the nanoscale, but the issue of excessive heat generation in highly integrated circuits persists. Therefore, it is essential to investigate the thermal durability of MoS<sub>2</sub> under various heating conditions and its impact on physical properties and device performance. In this study, we systematically investigated the oxidation behavior and related physical property variations of CVD-grown MoS<sub>2</sub> monolayers by baking them at different temperatures. It was clearly revealed that high-temperature baking induces <em>p</em>-doping and structural deformation, significantly altering optical and electrical properties. Despite the degradation in device performance, reduced interfacial Coulomb scattering was observed, suggesting potential for improved device stability. This study underscores the importance of understanding thermal stability to accelerate the development of 2D semiconductors for next-generation electronic devices.</div></div>","PeriodicalId":11037,"journal":{"name":"Current Applied Physics","volume":"70 ","pages":"Pages 61-68"},"PeriodicalIF":2.4,"publicationDate":"2024-11-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142697807","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Sanjith Unithrattil , Taewon Min , Gopinathan Anoop , Jun Young Lee , Tae Yeon kim , Shibnath Samanta , Yubo Qi , Jiahao Zhang , Seung Hyun Hwang , Hyeon Jun Lee , Kun Guo , Su Yong Lee , Yasuhiko Imai , Osami Sakata , Keisuke Shimizu , Kei Shigematsu , Hajime Hojo , Kui Yao , Masaki Azuma , Jaekwang Lee , Ji Young Jo
{"title":"Nanosecond electric pulse-induced ultrafast piezoelectric responses in Co3+ substituted BiFeO3 epitaxial thin films","authors":"Sanjith Unithrattil , Taewon Min , Gopinathan Anoop , Jun Young Lee , Tae Yeon kim , Shibnath Samanta , Yubo Qi , Jiahao Zhang , Seung Hyun Hwang , Hyeon Jun Lee , Kun Guo , Su Yong Lee , Yasuhiko Imai , Osami Sakata , Keisuke Shimizu , Kei Shigematsu , Hajime Hojo , Kui Yao , Masaki Azuma , Jaekwang Lee , Ji Young Jo","doi":"10.1016/j.cap.2024.11.012","DOIUrl":"10.1016/j.cap.2024.11.012","url":null,"abstract":"<div><div>Understanding the ultra-fast dynamics of ferroelectric materials is essential for advancing the development of next-generation high speed electronic and photonic devices. Here, the ultrafast piezoelectric response of cobalt-substituted BiFeO<sub>3</sub> (BiFe<sub>1-<em>x</em></sub>Co<sub><em>x</em></sub>O<sub>3</sub>) with <em>x</em> = 0.15, consisting of morphotropic phase boundary of monoclinic M<sub>C</sub> and M<sub>A</sub> –type phases is investigated. The real-time piezoelectric response in (001)-oriented BiFe<sub>0.85</sub>Co<sub>0.15</sub>O<sub>3</sub> (BFCO) epitaxial thin film was monitored using the time-resolved X-ray microdiffraction technique under an applied electric field with pulse widths 70 ns and 100 ns. The BFCO thin film yielded a high piezoelectric strain of approximately 0.53 % along [001] direction, with a giant <em>c</em>/<em>a</em> ratio (∼1.26) at an electric field of 1.3 MV/cm and a pulse width of 100 ns, with a piezoelectric coefficient (<span><math><mrow><msub><mi>d</mi><mn>33</mn></msub></mrow></math></span>) of 40 pm/V. This finding is an important step towards the development of a high performance lead-free piezoelectric material for ultrafast operations in advanced technological applications.</div></div>","PeriodicalId":11037,"journal":{"name":"Current Applied Physics","volume":"70 ","pages":"Pages 76-80"},"PeriodicalIF":2.4,"publicationDate":"2024-11-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142720528","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Observation of anomalous Nernst effect in non-collinear antiferromagnets","authors":"Asif Ullah, Thanh-Huong Thi Nguyen, Sanghoon Kim","doi":"10.1016/j.cap.2024.11.011","DOIUrl":"10.1016/j.cap.2024.11.011","url":null,"abstract":"<div><div>The field of spin caloritronics, which explores the interplay between spin current and thermal effects, is a promising path for new energy-efficient-electronic devices. However, current thermoelectric technologies are limited by conventional material choices and device designs. Antiferromagnetic materials, with their unique spin structure and magnetic characteristics, provide new opportunities for enhanced thermoelectric performance through spin-dependent effects. This review covers origin and measurement methodologies of anomalous Nernst effect, focusing on non-collinear antiferromagnets. By presenting insights into the relationship between electronic structure and thermoelectric performance as well as their practical measurements, this review aims to pave the way for developing AFM-based thermoelectric devices in advanced energy technologies.</div></div>","PeriodicalId":11037,"journal":{"name":"Current Applied Physics","volume":"70 ","pages":"Pages 51-60"},"PeriodicalIF":2.4,"publicationDate":"2024-11-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142698501","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Yu Chen, Guihong Song, Zhihao Ben, Yusheng Wu, Junhua You
{"title":"Improved thermoelectric properties of the β-Cu2+xSe/CuInSe2 multilayer films by layer interface scattering","authors":"Yu Chen, Guihong Song, Zhihao Ben, Yusheng Wu, Junhua You","doi":"10.1016/j.cap.2024.11.010","DOIUrl":"10.1016/j.cap.2024.11.010","url":null,"abstract":"<div><div>The β-Cu<sub>2+x</sub>Se/CuInSe<sub>2</sub> multilayer films with different modulation period were prepared and studied. The results showed that the deposited films possessed obvious layered structure. The room temperature carrier concentration, mobility, electrical conductivity and thermal conductivity decreased, but the Seebeck coefficient and power factor and relative thermoelectric figure of merit increased with reducing modulation period of deposited β-Cu<sub>2-x</sub>Se/CuInSe<sub>2</sub> multilayer films. The linear reduction of carrier concentration and mobility and the decrease in thermal conductivity with modulation period was attributed to the scattering of carriers and phonons by layer interface and grain boundary, respectively. The sample with the smallest modulation period (160 nm) possessed the highest power factor of ∼0.74 at room temperature and ∼1.56 mW m<sup>−1</sup> K<sup>−2</sup> at 405 °C. The insertion of heterogeneous layer into films is an effective method to increase Seebeck coefficient and decrease thermal conductivity, thus increasing thermoelectric figure of merit of films.</div></div>","PeriodicalId":11037,"journal":{"name":"Current Applied Physics","volume":"70 ","pages":"Pages 1-10"},"PeriodicalIF":2.4,"publicationDate":"2024-11-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142698494","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Impact analysis of various types of simulated multiple scattering matrices on the numerical simulation of high-resolution imaging in scattering media","authors":"Ye-Ryoung Lee","doi":"10.1016/j.cap.2024.11.004","DOIUrl":"10.1016/j.cap.2024.11.004","url":null,"abstract":"<div><div>Optical techniques are essential in biomedical research, enabling high-resolution, non-invasive imaging of biological tissues. However, imaging depth in optical microscopy is limited by multiple scattering in scattering media, such as biological tissues. Various methods have been developed to overcome this limitation, and numerical simulations have played an important role in developing new imaging techniques. Traditional simulations often use simple random matrices to represent multiple-scattered waves, which overly simplifies their behavior and may impact the accuracy of image quality assessments. In this study, we introduce various types of simulated multiple scattering matrices to better capture the characteristics of scattered waves. We systematically analyze the correlation properties of these matrices and evaluate their impact on high-resolution imaging quality. This work provides a foundation for selecting appropriate matrix types for simulating multiple scattering effects, aiding in the effective testing and validation of new microscopy techniques in scattering media.</div></div>","PeriodicalId":11037,"journal":{"name":"Current Applied Physics","volume":"70 ","pages":"Pages 21-26"},"PeriodicalIF":2.4,"publicationDate":"2024-11-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142697805","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Near-field infrared spectroscopy: Advanced research method in thin film analysis","authors":"Jiho Kim , Boknam Chae , Sangsul Lee","doi":"10.1016/j.cap.2024.11.002","DOIUrl":"10.1016/j.cap.2024.11.002","url":null,"abstract":"<div><div>This article introduces several cases of s-SNOM (Scattering-type scanning near-field optical microscopy) based on a SPM (Scanning probe microscopy) for chemical thin film. A highly concentrated near-field infrared performs the chemical analysis of s-SNOM at the sharp apex of the metal-coated atomic microscope tip. This attractive technique, which provides both surface morphology and chemical information of the material simultaneously, various studies have been published, including surface polariton propagation, Moire superlattice, and ballistic valley transport. Further, s-SNOM successfully visualized the formation of lamellar nanostructures of BCP and the latent image of photoresist formed by EUV (extreme ultraviolet). These results were cross-validated through traditional GIWAXS (Grazing-incidence wide-angle X-ray scattering) and FTIR (Fourier transform infrared) analysis. s-SNOM is a useful tool for providing new insights into material analysis by visualizing nanoscale chemical information of local regions that conventional measurements could not confirm.</div></div>","PeriodicalId":11037,"journal":{"name":"Current Applied Physics","volume":"70 ","pages":"Pages 41-50"},"PeriodicalIF":2.4,"publicationDate":"2024-11-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142698500","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Hwiwon Seo , Haneul Lee , Ji-Won Kwon , Gwanjoong Kim , Ingyu Lee , Gon-Ho Kim
{"title":"Analysis of electron thermal properties in Ar/O2 inductively coupled plasmas: A global model simulation using Langmuir probe data","authors":"Hwiwon Seo , Haneul Lee , Ji-Won Kwon , Gwanjoong Kim , Ingyu Lee , Gon-Ho Kim","doi":"10.1016/j.cap.2024.11.003","DOIUrl":"10.1016/j.cap.2024.11.003","url":null,"abstract":"<div><div>This study investigates the electron thermal properties in Argon and Ar/O2 inductively coupled plasmas using global model based on Langmuir probe data. The sensor-data driven global model (GM) is improved to simulate the power coupling efficiency and an electron energy distribution simultaneously. It reveals that the heating characteristic changes the thermal state and radical generation with input power, pressure and gas mixture ratio. The analysis results of probe data from the global model provide information on the plasma thermal characteristics under efficient operating conditions of process plasma. It provides the advantage of offering insights into the causes of variations in the plasma thermal equilibrium state with operating conditions in ICP, which are limited to obtain from the sensor or the general GM. This makes it highly promising as a simulation method for developing process recipes.</div></div>","PeriodicalId":11037,"journal":{"name":"Current Applied Physics","volume":"70 ","pages":"Pages 27-40"},"PeriodicalIF":2.4,"publicationDate":"2024-11-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142697806","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Highly selective dual gas (NO & NO2) sensing depended on the operating temperature of WO3 thin films sputtered at room temperature","authors":"Charu Dwivedi , Stuti Srivastava , Preetam Singh","doi":"10.1016/j.cap.2024.11.009","DOIUrl":"10.1016/j.cap.2024.11.009","url":null,"abstract":"<div><div>We have studied the effect of film thickness (120, 180, and 286 nm) on the dual gas (NO & NO<sub>2</sub>) sensing performance of DC magnetron sputtered WO<sub>3</sub> thin films deposited at room temperature. WO<sub>3</sub> shows strong absorption from visible light to the infrared region. An unusual peak originates at 467.6 nm (film thickness 286 nm) instead of a broadband tail, usually found in WO<sub>3</sub>, which has been linked with oxygen vacancies. A high response of ∼196 at 150 °C for 50 ppm NO and ∼50 at 250 °C for 50 ppm NO<sub>2</sub> is achieved for 286 nm film, which can be associated with Localized Surface Plasmon Resonance while a low response/recovery time of ∼39s/99s is obtained for 120 nm film at 200 °C for NO gas, which is its best operating temperature too (sensor response ∼100). Even under a high humidity (90 %) environment, the sensor detected 50 ppm of NO.</div></div>","PeriodicalId":11037,"journal":{"name":"Current Applied Physics","volume":"69 ","pages":"Pages 70-80"},"PeriodicalIF":2.4,"publicationDate":"2024-11-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142698212","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}