Hybrid ZnO/GaN distributed Bragg reflectors grown by plasma-assisted molecular beam epitaxy
Artikel i vetenskaplig tidskrift, 2016

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.






David Adolph

Chalmers, Mikroteknologi och nanovetenskap (MC2), Fotonik

Reza R. Zamani

Lunds universitet

Kimberly A. Dick

Lunds universitet

Tommy Ive

Chalmers, Mikroteknologi och nanovetenskap (MC2), Fotonik

APL Materials

2166-532X (eISSN)

Vol. 4 8 086106- 086106


Atom- och molekylfysik och optik


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