Article
Energy & Fuels
Xinyu Wang, Kun Gao, Dacheng Xu, Kun Li, Chunfang Xing, Xinliang Lou, Zhaojun Su, Xinbo Yang
Summary: Surface passivation is improved by using a boron oxide/aluminum oxide stack (BOx/Al2O3) on c-Si surfaces. The BOx/Al2O3 stacks show superior passivation quality compared to Al2O3 single layers after annealing. The optimized BOx/Al2O3 passivation stack achieves very low dark current densities on n-type and p-type Cz wafers, as well as boron-doped p+ emitters.
SOLAR ENERGY MATERIALS AND SOLAR CELLS
(2023)
Article
Physics, Applied
Jiarui Gong, Zheyang Zheng, Daniel Vincent, Jie Zhou, Jisoo Kim, Donghyeok Kim, Tien Khee Ng, Boon S. S. Ooi, Kevin J. J. Chen, Zhenqiang Ma
Summary: Ultrathin oxides and ultrathin nitrides play a crucial role in lattice-mismatched semiconductor heterostructures formed by semiconducting grafting approach. Available by atomic layer deposition, these dielectrics satisfy the surface passivation and quantum tunneling requirements for semiconductor grafting. Understanding the band parameters between ultrathin oxides or nitrides and GaN can guide the selection of interfacial dielectrics for grafted GaN-based devices.
JOURNAL OF APPLIED PHYSICS
(2022)
Article
Nanoscience & Nanotechnology
Mari Napari, Tahmida N. Huq, David J. Meeth, Mikko J. Heikkil, Kham M. Niang, Han Wang, Tomi Iivonen, Haiyan Wang, Markku Leskela, Mikko Ritala, Andrew J. Flewitt, Robert L. Z. Hoye, Judith L. MacManus-Driscoll
Summary: High-performance p-type oxide thin film transistors (TFTs) have great potential for semiconductor applications, but often suffer from low hole mobility and high off-state currents. By applying a thin ALD Al2O3 passivation layer on the Cu2O channel and vacuum annealing, the TFT switching characteristics can be improved. Characterization by TEM-EDX and XPS shows that Al2O3 deposition on Cu2O reduces surface and forms a CuAlO2 interfacial layer. This, along with field-effect passivation, leads to improved TFT performance by reducing trap states and electron accumulation in the off-state.
ACS APPLIED MATERIALS & INTERFACES
(2021)
Article
Engineering, Chemical
Julia Hartig, Hannah C. Howard, Tanner J. Stelmach, Alan W. Weimer
Summary: Continuous vibrating spatial particle ALD reactors were developed for high powder throughput with minimized footprint. The reactors operate below fluidization using linear vibration, and discrete element-method simulations were performed to study solid flow behavior. High-frequency excitations and sticking avoidance in horizontal conveyors at low accelerations were revealed, leading to a proposed novel sawtooth excitation for cohesive fine powders convection at low flow velocities.
Article
Energy & Fuels
A. Wratten, S. L. Pain, A. Yadav, E. Khorani, T. Niewelt, L. Black, G. Bartholazzi, D. Walker, N. E. Grant, J. D. Murphy
Summary: This study investigates the potential of ultra-thin HfO2 films grown by atomic layer deposition for passivating contacts to silicon. It specifically focuses on variations in film thickness and post-deposition annealing temperature. The results show that 2.2 nm thick films annealed at 475 degrees C exhibit the highest passivation quality. The effective work function of the films also decreases with decreasing thickness. A post-deposition annealing process reduces the effective work function further. The study also examines the contact resistivity in a passivating contact structure utilizing HfO2 and finds a temperature dependence on the annealing process. The lowest resistance is achieved below 375 degrees C.
SOLAR ENERGY MATERIALS AND SOLAR CELLS
(2023)
Article
Nanoscience & Nanotechnology
Abigail R. Meyer, Rohan P. Chaukulkar, Noemi Leick, William Nemeth, David L. Young, Paul Stradins, Sumit Agarwal
Summary: In this study, the atomistic-level mechanism for the chemical passivation of the monocrystalline Si surface with thermally annealed Al2O3 was investigated using in situ infrared spectroscopy and photoconductance decay measurements. The results showed that surface Si-H bonds are preserved after the ALD of Al2O3 on H-terminated Si, and restructuring occurs at the c-Si/Al2O3 interface during annealing to form interfacial SiOx. Isotope labeling was used to differentiate interfacial SiD bonds on the c-Si surface from H incorporated in Al2O3, and no net migration of atomic H or D from Al2O3 to the c-Si/Al2O3 interface was observed within the sensitivity of the infrared setup. Passivation studies were also conducted on c-Si/SiO2/Al2O3 stacks, revealing that an O-2-containing atmosphere led to the best surface chemical passivation.
ACS APPLIED NANO MATERIALS
(2021)
Article
Engineering, Electrical & Electronic
Juan Wang, Guoqing Shao, Genqiang Chen, Xiuliang Yan, Qi Li, Wangzhen Song, Yanfeng Wang, Zhangcheng Liu, Shuwei Fan, Chaoyang Zhang, Hong-Xing Wang
Summary: In this study, Zr/p-diamond Schottky barrier diodes with and without a ultrathin atomic layer-deposited Al2O3 interlayer were fabricated. The insertion of Al2O3 layer led to higher Schottky barrier height and breakdown voltage, attributed to the effective reduction of interface state density. This work provides a simple method to passivate the diamond surface and modulate the barrier heights of diamond SBDs.
IEEE TRANSACTIONS ON ELECTRON DEVICES
(2021)
Article
Chemistry, Multidisciplinary
Amirhossein Mahtabani, Damiano La Zara, Rafal Anyszka, Xiaozhen He, Mika Paajanen, J. Ruud van Ommen, Wilma Dierkes, Anke Blume
Summary: The gas-phase modification process improved control over the thickness and uniformity of the deposited layers on nanoparticles, allowing for the introduction of versatile functionalized organic layers on the surface of nanoparticles in a controlled manner.
Article
Chemistry, Physical
Jose Antonio Diaz-Lopez, Jordi Guilera, Marti Biset-Peiro, Dan Enache, Gordon Kelly, Teresa Andreu
Summary: The technical feasibility of passivating a Co/gamma-Al2O3 catalyst using atomic layer deposition (ALD) to reduce deactivation rate during Fischer-Tropsch synthesis (FTS) was explored in this study. The results showed that 3 to 6 ALD cycles effectively reduced deactivation of the catalyst, while 10 cycles caused blockage of the active phase and a decrease in catalytic activity. This research demonstrates the potential of ALD as a method to improve catalyst stability in FTS processes.
Article
Nanoscience & Nanotechnology
Azina Rahmani, Maksim A. Sultanov, Kemah Kamiru-White, Lorianne R. Shultz-Johnson, Brian E. Butkus, Shaohua Xie, Fudong Liu, Diep T. H. Nguyen, Noeimie Wilson-Faubert, Ali Nazemi, Parag Banerjee, Lei Zhai, Massimiliano Delferro, Jianguo Wen, Titel Jurca
Summary: Galvanic exchange and atomic layer deposition techniques were used to prepare ultralow loading Pt catalysts with high stability and recyclability. The catalysts showed high activity towards various functionalized styrenes and excellent tolerance towards substituents.
ACS APPLIED MATERIALS & INTERFACES
(2023)
Article
Energy & Fuels
Xiao-Ying Zhang, Jing Han, Yao-Tian Wang, Yu-Jiao Ruan, Wan-Yu Wu, Dong-Sing Wuu, Juan Zuo, Feng-Min Lai, Shui-Yang Lien, Wen-Zhang Zhu
Summary: Hafnium oxide (HfO2) thin film is studied as a passivation layer for crystalline silicon (c-Si). The electrical characterization and measurements of HfO2 films on P-type and N-type c-Si were conducted. Post annealing in different gas ambients was performed. The results reveal the potential of HfO2 for field effect and chemical passivation. The impacts of post-annealing gas ambient on passivation qualities on Si by HfO2 thin films are systematically studied.
SOLAR ENERGY MATERIALS AND SOLAR CELLS
(2023)
Article
Materials Science, Multidisciplinary
Minjae Kim, Malik Abdul Rehman, Kyung-Mun Kang, Yue Wang, Sewon Park, Hong-Sub Lee, Sanjib Baran Roy, Seung-Hyun Chun, Chabungbam Akendra Singh, Seong Chan Jun, Hyung-Ho Park
Summary: Graphene-based solar cells using a metal-insulator-semiconductor (MIS) junction face challenges in long-term stability, surface recombination, and defects. A method for interfacial passivation of Al2O3 with NH3 or H2O2, and co-passivation with NH3 and H2O2, has been developed to minimize surface recombination. The co-passivated Al2O3 layer enhances the growth of graphene and improves solar cell performance, leading to a significant efficiency enhancement.
APPLIED MATERIALS TODAY
(2022)
Article
Chemistry, Physical
Eunyoung Choi, Jin-Won Lee, Miguel Anaya, Alessandro Mirabelli, Hongjae Shim, Joseph Strzalka, Jongchul Lim, Siwon Yun, Milos Dubajic, Jihoo Lim, Jan Seidel, Raphael Edem Agbenyeke, Chang Gyoun Kim, Nam Joong Jeon, Arman Mahboubi Soufiani, Helen Hejin Park, Jae Sung Yun
Summary: Long-chain organic halide salts are widely used in perovskite-based optoelectronic devices for surface passivation. By introducing aluminum oxide (AlOx) onto octylammonium iodide (OAI) through atomic layer deposition, the benefits of organic halide salts can be utilized without generating undesired defects. The OAI/AlOx devices show improved performance and photo-stability compared to the treated devices, with a diffusion of aluminum from AlOx into the perovskite contributing to uniform carrier transport. In addition, light-induced two-dimensional perovskite formation is observed on OAI/AlOx, which prevents the loss of OA cations and suppresses the light-induced degradation of the devices.
ADVANCED ENERGY MATERIALS
(2023)
Article
Materials Science, Multidisciplinary
Wilhelmus J. H. Berghuis, Jimmy Melskens, Bart Macco, Roel J. Theeuwes, Marcel A. Verheijen, Wilhelmus M. M. Kessels
Summary: The study investigated the passivation effect of Al2O3 on Ge surfaces and found that Al2O3 prepared by ALD can achieve low surface recombination velocity. The influence of different process parameters on the passivation effect was discussed.
JOURNAL OF MATERIALS RESEARCH
(2021)
Article
Physics, Applied
Shouqiang Lai, Wansheng Lin, Jinlan Chen, Tingwei Lu, Shibiao Liu, Yi Lin, Yijun Lu, Yue Lin, Zhong Chen, Hao-Chung Kuo, Weijie Guo, Tingzhu Wu
Summary: This study investigates the photoelectric characteristics of mini-light-emitting-diodes (mini-LEDs) with sidewall passivation by atomic layer deposition (ALD) using spectrometer-based spectroradiometer and microscopic hyperspectral imaging (mu-HSI) techniques. The results show that the ALD sidewall passivation can enhance the temperature stability and light extraction efficiency of the mini-LEDs.
JOURNAL OF PHYSICS D-APPLIED PHYSICS
(2022)
Review
Materials Science, Multidisciplinary
Yun Li, Yingfei Xiong, Huizhi Yang, Kun Cao, Rong Chen
JOURNAL OF MATERIALS RESEARCH
(2020)
Article
Chemistry, Multidisciplinary
Yun Li, Kun Cao, Ying fei Xiong, Huizhi Yang, Yinghao Zhang, Yuan Lin, Binze Zhou, Jing Huang, Rong Chen
ADVANCED MATERIALS INTERFACES
(2020)
Article
Chemistry, Physical
Yao Jing, Kun Cao, Binze Zhou, Shicai Geng, Yanwei Wen, Bin Shan, Rong Chen
CHEMISTRY OF MATERIALS
(2020)
Article
Materials Science, Coatings & Films
Jiaming Cai, Marc J. M. Merkx, Yuxiao Lan, Yao Jing, Kun Cao, Yanwei Wen, Wilhelmus M. M. Kessels, Adriaan J. M. Mackus, Rong Chen
Summary: This study investigates the influence of an oxidizing coreactant and reaction temperature on the selective growth of FeOx on the surfaces of Pt nanoparticles. Results show that using O-3 as the coreactant at low temperature allows for selective deposition on low coordination edge sites, while using O-2 at higher temperatures does not exhibit selectivity. Energy barrier differences and temperature dependence play key roles in the edge-selective growth of FeOx on Pt.
JOURNAL OF VACUUM SCIENCE & TECHNOLOGY A
(2021)
Article
Chemistry, Multidisciplinary
Yun Li, Yingfei Xiong, Weiran Cao, Qianqian Zhu, Yuan Lin, Yinghao Zhang, Mengjia Liu, Fan Yang, Kun Cao, Rong Chen
Summary: In this study, PDMS/Al2O3 nanolaminates were developed to protect OLEDs from moisture erosion, with optimized sublayer thickness and interfaces. The use of O-2 plasma pretreatment and electrical calcium test improved the barrier properties, and the mechanical stability was further enhanced by introducing a top epoxy layer. The operational lifetime of blue OLEDs encapsulated with the nanolaminates significantly increased, demonstrating improved stability and reliability.
ADVANCED MATERIALS INTERFACES
(2021)
Article
Nanoscience & Nanotechnology
Zhang Liu, Jiaqiang Yang, Yanwei Wen, Yuxiao Lan, Limin Guo, Xi Chen, Kun Cao, Rong Chen, Bin Shan
Summary: This study investigates the mechanism of CO PROX reaction on Co3O4 supported single Pt atom through first-principles based microkinetic analysis. The research finds that H2 prereduction treatment effectively mitigates the CO poisoning effect and surface H atoms assist in improving the activity and selectivity at low temperatures.
ACS APPLIED MATERIALS & INTERFACES
(2022)
Article
Materials Science, Coatings & Films
Yuxiao Lan, Yanwei Wen, Yicheng Li, Jiaqiang Yang, Kun Cao, Bin Shan, Rong Chen
Summary: Selective atomic layer deposition has great potential in the manufacturing of nanoelectronics. This study investigates the interaction between Mn precursors and Pt surfaces and reveals the effect of ligands on the selective growth of MnOx on Pt surfaces.
JOURNAL OF VACUUM SCIENCE & TECHNOLOGY A
(2023)
Article
Materials Science, Coatings & Films
Rong Chen, Zilian Qi, Yingfei Xiong, Yicheng Li, Xiaodong Zhang, Kun Cao
Summary: Ferroelectric thin-film bilayers consisting of Pb(Mg1/3Nb2/3)O-3-PbTiO3 (PMN-PT) and PbZr0.52Ti0.48O3 (PZT) were successfully grown on a flexible mica substrate using pulsed laser deposition. The bilayer exhibits enhanced ferroelectric properties and excellent resistance against mechanical bending fatigue. These improvements are attributed to enhanced spontaneous polarizations, increased interfacial potential barrier against leakage, and suppressed diffusion of Nb or Mg across the interface.
JOURNAL OF VACUUM SCIENCE & TECHNOLOGY A
(2023)
Article
Engineering, Electrical & Electronic
Zhiyong Lei, Min Wang, Xiao-Dong Zhang, Kun Cao, Zhaojie Wang, Yanwei Wen, Rong Chen
Summary: In this study, high-performance blue perovskite quantum dots (PQDs) with a tunable emission wavelength were successfully obtained using a ligand-assisted anion exchange strategy with the assistance of didodecydimethyammonium chloride (DDAC) ligand. The anchored DDAC ligand passivates the surface vacancies of the PQD, enabling a high efficiency emission of blue light. The well-controlled chlorinestoichiometry of the PQD allows fine-tuning of its photoluminescence and electroluminescence spectra. The fabricated PQDs LED device shows high external quantum efficiency in the blue light range, showcasing the importance of this research for the development of blue PQDs LED.
ACS APPLIED ELECTRONIC MATERIALS
(2023)
Article
Materials Science, Multidisciplinary
Zerui Jin, Huajun Zhou, Xiaodong Zhang, Kun Cao, Rong Chen
Summary: Integrated nonreciprocal photonic devices for optical communication face the challenge of on-chip monolithic integration of magneto-optical materials onto silicon. A MgO interfacial layer is introduced through pulsed laser deposition (PLD) to tackle the material incompatibilities between silicon substrate and magneto-optical thin films of yttrium iron garnet (YIG). The amorphous MgO interfacial layer with a thickness of 40 nm effectively prevents interdiffusion across YIG/Si and promotes the growth of a high-density, high-phase-purity polycrystalline garnet structure in the YIG/Ce:YIG bilayer. The modified chemistry and microstructure in YIG/Ce:YIG result in enhanced magneto-optical properties and increased infrared transmission.
ACS MATERIALS LETTERS
(2023)
Article
Engineering, Electrical & Electronic
Runqing Wu, Lincong Zhang, Kun Cao, Song Tian, Xiao-Dong Zhang, Rong Chen
Summary: Measurement of gas permeation is crucial for various applications, and a high-sensitivity gas measurement system based on quadrupole mass spectrometry (QMS) was calibrated using standard flows of different gases. The flow rate of water vapor was found to be reduced by about 28% due to capillary condensation. The calibration improved the reliability of the QMS-based instrument for measuring water vapor transmission rate (WVTR) at low levels.
IEEE TRANSACTIONS ON INSTRUMENTATION AND MEASUREMENT
(2023)
Article
Engineering, Electrical & Electronic
Shicai Geng, Yanwei Wen, Binze Zhou, Zhaojie Wang, Zhaojin Wang, Pengfei Wang, Yao Jing, Kun Cao, Kai Wang, Rong Chen
Summary: The study successfully achieved highly efficient and stable perovskite quantum dot light-emitting diodes by using an inorganic ZnBr2 ligand and introducing an Al2O3 buffer layer. The interface engineering through ALD technology improved the external quantum efficiency and lifetime of the devices.
ACS APPLIED ELECTRONIC MATERIALS
(2021)
Article
Nanoscience & Nanotechnology
Yao Jing, Marc J. M. Merkx, Jiaming Cai, Kun Cao, Wilhelmus M. M. Kessels, Adriaan J. M. Mackus, Rong Chen
ACS APPLIED MATERIALS & INTERFACES
(2020)
Review
Engineering, Manufacturing
Rong Chen, Yi-Cheng Li, Jia-Ming Cai, Kun Cao, Han-Bo-Ram Lee
INTERNATIONAL JOURNAL OF EXTREME MANUFACTURING
(2020)
Article
Engineering, Electrical & Electronic
Chenchen Jiang, Kun Cao, Binze Zhou, Yanwei Wen, Bin Shan, Rong Chen
ACS APPLIED ELECTRONIC MATERIALS
(2020)