1
|
Gong R, Azrak E, Castro C, Duguay S, Pareige P, Roca I Cabarrocas P, Chen W. Controlling solid-liquid-solid GeSn nanowire growth modes by changing deposition sequences of a-Ge:H layer and SnO 2nanoparticles. NANOTECHNOLOGY 2021; 32:345602. [PMID: 33910185 DOI: 10.1088/1361-6528/abfc72] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/12/2021] [Accepted: 04/27/2021] [Indexed: 06/12/2023]
Abstract
Alloying Ge with Sn is one of the promising ways for achieving Si compatible optoelectronics. Here, GeSn nanowires (NWs) are realized via nano-crystallization of a hydrogenated amorphous Ge (a-Ge:H) layer with the help of metal Sn droplets. The full process consists of three steps: (1) SnO2nanoparticle (NP) reduction in a hydrogen plasma to produce Sn catalyst; (2) a-Ge:H deposition at 120 °C and (3) annealing. GeSn alloys with rich morphologies such as discrete nanocrystals (NCs), random, and straight NWs were successfully synthesized by changing process conditions. We show that annealing under Ar plasma favors the elaboration of straight GeSn NWs in contrast to the conventional random GeSn NWs obtained when annealing is performed under a H2atmosphere. Interestingly, GeSn in the form of discrete NCs can be fabricated during the deposition of a-Ge:H at 180 °C. Even more, the synthesis of out-of-plane GeSn NWs has been demonstrated by reversing the deposition sequence of SnO2NPs and a-Ge:H layer.
Collapse
Affiliation(s)
- Ruiling Gong
- School of Physical Science and Technology, Ningbo University, Ningbo 315211, People's Republic of China
| | - Edy Azrak
- GPM, Université et INSA de Rouen, CNRS, Normandie Université, Saint Etienne du Rouvray, F-76800, France
| | - Celia Castro
- GPM, Université et INSA de Rouen, CNRS, Normandie Université, Saint Etienne du Rouvray, F-76800, France
| | - Sébastien Duguay
- GPM, Université et INSA de Rouen, CNRS, Normandie Université, Saint Etienne du Rouvray, F-76800, France
| | - Philippe Pareige
- GPM, Université et INSA de Rouen, CNRS, Normandie Université, Saint Etienne du Rouvray, F-76800, France
| | - Pere Roca I Cabarrocas
- LPICM, CNRS, Ecole Polytechnique, Institut Polytechnique de Paris, F-91128 Palaiseau, France
| | - Wanghua Chen
- School of Physical Science and Technology, Ningbo University, Ningbo 315211, People's Republic of China
| |
Collapse
|
2
|
Kim JJ, Lim CR, Reddy BM, Park SE. Hierarchical porous organic polymer as an efficient metal-free catalyst for acetalization of carbonyl compounds with alcohols. MOLECULAR CATALYSIS 2018. [DOI: 10.1016/j.mcat.2017.10.022] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
|
3
|
Zhao S, Kad B, Wehrenberg CE, Remington BA, Hahn EN, More KL, Meyers MA. Generating gradient germanium nanostructures by shock-induced amorphization and crystallization. Proc Natl Acad Sci U S A 2017; 114:9791-9796. [PMID: 28847926 PMCID: PMC5604032 DOI: 10.1073/pnas.1708853114] [Citation(s) in RCA: 37] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Gradient nanostructures are attracting considerable interest due to their potential to obtain superior structural and functional properties of materials. Applying powerful laser-driven shocks (stresses of up to one-third million atmospheres, or 33 gigapascals) to germanium, we report here a complex gradient nanostructure consisting of, near the surface, nanocrystals with high density of nanotwins. Beyond there, the structure exhibits arrays of amorphous bands which are preceded by planar defects such as stacking faults generated by partial dislocations. At a lower shock stress, the surface region of the recovered target is completely amorphous. We propose that germanium undergoes amorphization above a threshold stress and that the deformation-generated heat leads to nanocrystallization. These experiments are corroborated by molecular dynamics simulations which show that supersonic partial dislocation bursts play a role in triggering the crystalline-to-amorphous transition.
Collapse
Affiliation(s)
- Shiteng Zhao
- Materials Science and Engineering Program, University of California, San Diego, La Jolla, CA 92093
| | - Bimal Kad
- Department of Structural Engineering, University of California, San Diego, La Jolla, CA 92093
| | | | | | - Eric N Hahn
- Materials Science and Engineering Program, University of California, San Diego, La Jolla, CA 92093
| | | | - Marc A Meyers
- Materials Science and Engineering Program, University of California, San Diego, La Jolla, CA 92093;
- Department of Mechanical and Aerospace Engineering, University of California, San Deigo, La Jolla, CA 92093
- Department of Nanoengineering, University of California, San Deigo, La Jolla, CA 92093
| |
Collapse
|