Atomic layer-by-layer construction of Pd on nanoporous gold via underpotential deposition and displacement reaction

RSC Advances ◽  
2015 ◽  
Vol 5 (25) ◽  
pp. 19409-19417 ◽  
Author(s):  
Xuejiao Yan ◽  
Haiyan Xiong ◽  
Qingguo Bai ◽  
Jan Frenzel ◽  
Conghui Si ◽  
...  

Ultrathin Pd films with one to five atomic layers were decorated on nanoporous gold by underpotential deposition and galvanic displacement.

1997 ◽  
Vol 502 ◽  
Author(s):  
Ivan Bozovic ◽  
J. N. Eckstein ◽  
Natasha Bozovic ◽  
J. O'Donnell

ABSTRACTReal-time, in-situ surface monitoring by reflection high-energy electron diffraction (RHEED) has been the key enabling component of atomic-layer-by-layer molecular beam epitaxy (ALL-MBE) of complex oxides. RHEED patterns contain information on crystallographic arrangements and long range order on the surface; this can be made quantitative with help of numerical simulations. The dynamics of RHEED patterns and intensities reveal a variety of phenomena such as nucleation and dissolution of secondary-phase precipitates, switching between growth modes (layer-by-layer, step-flow), surface phase transitions (surface reconstruction, roughening, and even phase transitions induced by the electron beam itself), etc. Some of these phenomena are illustrated here, using as a case study our recent growth of atomically smooth a-axis oriented DyBa2Cu3O7 films.


2017 ◽  
Vol 139 (41) ◽  
pp. 14518-14525 ◽  
Author(s):  
Degao Wang ◽  
Matthew V. Sheridan ◽  
Bing Shan ◽  
Byron H. Farnum ◽  
Seth L. Marquard ◽  
...  

1995 ◽  
Vol 387 ◽  
Author(s):  
J. L. Hoyt ◽  
P. Kuo ◽  
K. Rim ◽  
J. J. Welser ◽  
R. M. Emerson ◽  
...  

AbstractMaterial and device challenges for Rapid Thermal Processing (RTP) of heterostructures are discussed, focusing on RTP-based epitaxy in the Si/Si1−xGex system. While RTP-based heteroepitaxy offers enhanced processing flexibility, it also poses significant challenges for temperature measurement and control. Several examples of Si/Si1−xGex device structures are discussed from the point of view of the sensitivity of device parameters to variations in layer thickness and composition. The measured growth kinetics for Si and Si1−xGex are then used to estimate growth temperature tolerances for these structures. Demanding applications are expected to require temperature control and uniformity to within 0.5°C.Future research challenges include the fabrication of structures with monolayer thickness control using self-limited growth techniques. Atomic layer epitaxy (ALE) is a well-known example of such a growth technique. In ALE, the wafer is cyclically exposed to different reactants, to achieve layer-by-layer growth. An RTP-based atomic layer epitaxy process, and its application to the growth of CdTe films, is briefly discussed. The extension to Column IV alloys follows readily. The RTP-based process enables self-limited growth for precursor combinations for which isothermal ALE is not feasible.


RSC Advances ◽  
2016 ◽  
Vol 6 (37) ◽  
pp. 31454-31461 ◽  
Author(s):  
Y. S. Yamamoto ◽  
Y. Fujime ◽  
N. Takahashi ◽  
S. Nakanishi ◽  
T. Itoh

Multi-element XPS depth profile analysis made clear that Ag nanoscale hexagonal columns formed by newly-discovered galvanic displacement reaction are covered with Cu compounds which prevent Ag columns from fusion, resulting in stable hotspots.


1993 ◽  
Vol 32 (Part 2, No. 2B) ◽  
pp. L236-L238 ◽  
Author(s):  
Kuninori Kitahara ◽  
Nobuyuki Ohtsuka ◽  
Toshihiko Ashino ◽  
Masashi Ozeki ◽  
Kazuo Nakajima

Crystals ◽  
2020 ◽  
Vol 10 (4) ◽  
pp. 291
Author(s):  
Alberto Perrotta ◽  
Julian Pilz ◽  
Roland Resel ◽  
Oliver Werzer ◽  
Anna Maria Coclite

Direct plasma enhanced-atomic layer deposition (PE-ALD) is adopted for the growth of ZnO on c-Si with native oxide at room temperature. The initial stages of growth both in terms of thickness evolution and crystallization onset are followed ex-situ by a combination of spectroscopic ellipsometry and X-ray based techniques (diffraction, reflectivity, and fluorescence). Differently from the growth mode usually reported for thermal ALD ZnO (i.e., substrate-inhibited island growth), the effect of plasma surface activation resulted in a substrate-enhanced island growth. A transient region of accelerated island formation was found within the first 2 nm of deposition, resulting in the growth of amorphous ZnO as witnessed with grazing incidence X-ray diffraction. After the islands coalesced and a continuous layer formed, the first crystallites were found to grow, starting the layer-by-layer growth mode. High-temperature ALD ZnO layers were also investigated in terms of crystallization onset, showing that layers are amorphous up to a thickness of 3 nm, irrespective of the deposition temperature and growth orientation.


Sign in / Sign up

Export Citation Format

Share Document