Hybrid ZnO/GaN distributed Bragg reflectors grown by plasma-assisted molecular beam epitaxy
(2016) In APL Materials 4(8).- Abstract
We demonstrate crack-free ZnO/GaN distributed Bragg reflectors (DBRs) grown by hybrid plasma-assisted molecular beam epitaxy using the same growth chamber for continuous growth of both ZnO and GaN without exposure to air. This is the first time these ZnO/GaN DBRs have been demonstrated. The Bragg reflectors consisted up to 20 periods as shown with cross-sectional transmission electron microscopy. The maximum achieved reflectance was 77% with a 32 nm wide stopband centered at 500 nm. Growth along both (0001) and (000 1) directions was investigated. Low-temperature growth as well as two-step low/high-temperature deposition was carried out where the latter method improved the DBR reflectance. Samples grown along the (0001) direction... (More)
We demonstrate crack-free ZnO/GaN distributed Bragg reflectors (DBRs) grown by hybrid plasma-assisted molecular beam epitaxy using the same growth chamber for continuous growth of both ZnO and GaN without exposure to air. This is the first time these ZnO/GaN DBRs have been demonstrated. The Bragg reflectors consisted up to 20 periods as shown with cross-sectional transmission electron microscopy. The maximum achieved reflectance was 77% with a 32 nm wide stopband centered at 500 nm. Growth along both (0001) and (000 1) directions was investigated. Low-temperature growth as well as two-step low/high-temperature deposition was carried out where the latter method improved the DBR reflectance. Samples grown along the (0001) direction yielded a better surface morphology as revealed by scanning electron microscopy and atomic force microscopy. Reciprocal space maps showed that ZnO(000 1)/GaN reflectors are relaxed whereas the ZnO(0001)/GaN DBRs are strained. The ability to n-type dope ZnO and GaN makes the ZnO(0001)/GaN DBRs interesting for various optoelectronic cavity structures.
(Less)
- author
- Adolph, David LU ; Zamani, Reza R. LU ; Dick, Kimberly A. LU and Ive, Tommy
- organization
- publishing date
- 2016-08-01
- type
- Contribution to journal
- publication status
- published
- subject
- in
- APL Materials
- volume
- 4
- issue
- 8
- article number
- 086106
- publisher
- American Institute of Physics (AIP)
- external identifiers
-
- wos:000383910000007
- scopus:84982095517
- ISSN
- 2166-532X
- DOI
- 10.1063/1.4960619
- language
- English
- LU publication?
- yes
- id
- 85353f67-69e0-4215-b7e7-7270696df86e
- date added to LUP
- 2016-12-09 14:46:01
- date last changed
- 2025-01-12 17:22:51
@article{85353f67-69e0-4215-b7e7-7270696df86e, abstract = {{<p>We demonstrate crack-free ZnO/GaN distributed Bragg reflectors (DBRs) grown by hybrid plasma-assisted molecular beam epitaxy using the same growth chamber for continuous growth of both ZnO and GaN without exposure to air. This is the first time these ZnO/GaN DBRs have been demonstrated. The Bragg reflectors consisted up to 20 periods as shown with cross-sectional transmission electron microscopy. The maximum achieved reflectance was 77% with a 32 nm wide stopband centered at 500 nm. Growth along both (0001) and (000 1) directions was investigated. Low-temperature growth as well as two-step low/high-temperature deposition was carried out where the latter method improved the DBR reflectance. Samples grown along the (0001) direction yielded a better surface morphology as revealed by scanning electron microscopy and atomic force microscopy. Reciprocal space maps showed that ZnO(000 1)/GaN reflectors are relaxed whereas the ZnO(0001)/GaN DBRs are strained. The ability to n-type dope ZnO and GaN makes the ZnO(0001)/GaN DBRs interesting for various optoelectronic cavity structures.</p>}}, author = {{Adolph, David and Zamani, Reza R. and Dick, Kimberly A. and Ive, Tommy}}, issn = {{2166-532X}}, language = {{eng}}, month = {{08}}, number = {{8}}, publisher = {{American Institute of Physics (AIP)}}, series = {{APL Materials}}, title = {{Hybrid ZnO/GaN distributed Bragg reflectors grown by plasma-assisted molecular beam epitaxy}}, url = {{http://dx.doi.org/10.1063/1.4960619}}, doi = {{10.1063/1.4960619}}, volume = {{4}}, year = {{2016}}, }