Ren Bin Yang

Bio: Ren Bin Yang is an academic researcher from Agency for Science, Technology and Research. The author has contributed to research in topics: Atomic layer deposition & Thin film. The author has an hindex of 4, co-authored 4 publications receiving 33 citations.

Giant Blistering of Nanometer-Thick Al2O3/ZnO Films Grown by Atomic Layer Deposition: Mechanism and Potential Applications

Abstract: Giant circular blisters of up to 300 μm diameter and 10 μm deflection have been produced on nanometer-thick Al2O3-on-ZnO stacks grown by atomic layer deposition at 150 °C followed by annealing at elevated temperatures. Their shape changes upon varied ambient pressures provide evidence that their formation is related to an anneal-induced outgassing combined with their impermeability. The former mainly occurs in the bottom ZnO layer that recrystallizes and releases residual hydroxide ions at elevated temperatures while the latter is dominantly contributed by the pinhole-free Al2O3 layer on top. Vibrations at a resonant frequency of ∼740 kHz are mechanically actuated and optically probed from an individual blister. By modulating the thickness and stacking sequence of Al2O3 and ZnO, we further demonstrate a localized circular film swelling upon electron-beam irradiation and its recovery after reducing the irradiation flux. The elastic blistering and the recoverable swelling of the nanometer-thick films repres...

Optimal Shell Thickness of Metal@Insulator Nanoparticles for Net Enhancement of Photogenerated Polarons in P3HT Films

Abstract: Embedding metal nanoparticles in the active layer of organic solar cells has been explored as a route for improving charge carrier generation, with localized field enhancement as a proposed mechanism. However, embedded metal nanoparticles can also act as charge recombination sites. To suppress such recombination, the metal nanoparticles are commonly coated with a thin insulating shell. At the same time, this insulating shell limits the extent that the localized enhanced electric field influences charge generation in the organic medium. It is presumed that there is an optimal thickness which maximizes field enhancement effects while suppressing recombination. Atomic Layer Deposition (ALD) was used to deposit Al2O3 layers of different thicknesses onto silver nanoparticles (Ag NPs), in a thin film of P3HT. Photoinduced absorption (PIA) spectroscopy was used to study the dependence of the photogenerated P3HT+ polaron population on the Al2O3 thickness. The optimal thickness was found to be 3–5 nm. This knowled...

Synthesis of doped, ternary, and quaternary materials by atomic layer deposition: a review

Abstract: In the past decade, atomic layer deposition (ALD) has become an important thin film deposition technique for applications in nanoelectronics, catalysis, and other areas due to its high conformality...

Atomic Layer Deposition of Two-Dimensional Layered Materials: Processes, Growth Mechanisms, and Characteristics

Abstract: Summary Since the discovery of graphene, there has been an ever-increasing interest in two-dimensional (2D) layered materials with exceptional properties. To this end, a variety of synthesis methods have been developed. However, it is still challenging to produce large-scale high-quality single-crystalline 2D materials. In this regard, atomic layer deposition (ALD) has recently shown great promise and has stimulated more and more research efforts, ascribed to its unique growth mechanism and distinguished capabilities to achieve nanoscale films with excellent uniformity, unrivaled conformality, and atomic-scale controllability. This review comprehensively summarizes recent progress on ALD for 2D atomic sheets, including 25 different materials and more than 80 ALD processes. This work highlights different technical routes to ALD, their precise controllability, and their underlying principles for 2D materials. It is expected that this work will help boost more research efforts for controllable growth of high-quality 2D materials via ALD.

Bilayer MoOX/CrOX Passivating Contact Targeting Highly Stable Silicon Heterojunction Solar Cells.

Abstract: Molybdenum oxide (MoOX, X < 3) has been successfully demonstrated as an efficient passivating hole-selective contact in crystalline Si (c-Si) heterojunction solar cells because of its large bandgap (∼3.2 eV) and work function (∼6.9 eV). However, the severe performance degradation coming from the instability of the MoOX and its interfaces has not been well addressed. In this work, we started with a c-Si(p)/MoOX heterojunction solar cell that yielded a power conversion efficiency (PCE) of 15.86%, in which the MoOX film was synthesized by industry-compatible atomic layer deposition (ALD). The initial PCE dropped to 10.20% after 2 days because of severe migration of O and Ag at the MoOX/Ag interface. We solved this by the insertion of a CrOX layer between the MoOX layer and the Ag electrode. The solar cell was found to be stable for more than 8 months in air because of the suppression of interface degradation. Our work demonstrates an effective way of improving the stability of silicon solar cells with transition metal oxide carrier selective contacts.