Molecular Beam Epitaxial Growth of ZnO on Si Substrate Using Ozone as an Oxygen Source

Abstract

Epitaxial ZnO films have been grown on Si (111) substrates by molecular beam epitaxy using ozone as an oxygen source. An initial deposition of a Zn layer followed by its oxidation produces a superior template for the subsequent ZnO growth. The reflection high-energy electron diffraction measurement suggests that the initial Zn layer and ZnO film are rotated by 30 with respect to the Si substrate orientation. The X-ray diffraction measurement reveals that the as-grown ZnO films are strongly coriented and include no rotational domains. Although there exists a small trace of ZnO (10 1 11) domains, it easily disappears upon annealing at 1100 C for 1 min after growth. Low-temperature photoluminescence measurements indicate that the emission property is improved significantly after annealing. The bound-exciton emission at 3.354 eV is dominant and its fullwidth at half maximum is as small as 11 meV.

CBE growth of high‐quality ZnO epitaxial layers

“…The above problems inspire the search for alternative sources of efficient oxidizing species for ZnO epitaxy. The use of reactive oxygen-containing compositions, like ozone [16], as oxidants for ZnO MBE could be a very attractive alternative to oxygen plasma cell. Recently, we reported the implementation of H 2 O 2 as an oxidant for MBE growth of ZnO on GaN template [17].…”

Molecular beam epitaxial growth of hexagonal ZnMgO films on Si(1 1 1) substrates using thin MgO buffer layer

“…Therefore, we have focused on the Si substrates for the growth of ZnO films [16][17][18]. The growth of epitaxial ZnO films on Si is, however, known to be a difficult task because the Si substrate surface is easily oxidized and the crystal quality of ZnO film grown on such a SiO x layer is considerably deteriorated.…”

“…The growth of epitaxial ZnO films on Si is, however, known to be a difficult task because the Si substrate surface is easily oxidized and the crystal quality of ZnO film grown on such a SiO x layer is considerably deteriorated. In order to prevent the Si substrate surface from being oxidized in the initial growth stage of ZnO, and improve the crystal quality of ZnO films, we have used two methods: initial Zn layer deposition followed by its oxidation [16,17] and initial Mg layer deposition followed by MgO growth [18]. Although the grown ZnO films exhibit very high photoluminescence (PL) efficiency by using the former method, they suffer from high density of micro-cracks along the principal axes on the Si(1 1 1) surface probably caused by the difference in the thermal expansion coefficients between ZnO and Si.…”

Study of the effect of plasma power on ZnO thin films growth using electron cyclotron resonance plasma-assisted molecular-beam epitaxy

“…Among these growth methods, MBE has some potential advantages, such as precise control of growth parameters and in situ characterization techniques. Although some other oxidants such as NO 2 [35], O 3 [36], and H 2 O 2 [37] were tried, O 2 plasma-assisted method is the mainstream for ZnO MBE growth. Radio frequency (RF) and electron cyclotron resonance (ECR) are the two main plasma generation approaches.…”