09:15 〜 09:30
▼ [13a-D215-2] Improved properties of low-resistive Al-doped ZnCdO thin films by MBE.
キーワード：ZnCdO, Molecular beam epictaxy, Thin film
Recently, a II-VI semiconductor material based on CdO (band gap energy of 2.3 eV) is expected to realize low resistive thin films at a low carrier concentration which can suppress a free carrier absorption and a plasma reflection, leading to a high transparency in long wavelength up to infrared region. Although the band gap of CdO is small for a transparent conductive oxide (TCO) application, it can be expanded by alloying with ZnO which has a band gap of ~3.3 eV. However, because CdO has a rocksalt (RS) structure (a=4.70 Å), whereas ZnO has a wurtzite (WZ) structure (a=3.25 Å, c=5.21 Å), the crystal structure of Zn1-xCdxO (ZnCdO) is expected to change at a certain Cd composition.
In the previous study, we have grown Al-doped ZnCdO thin films on MgO (100) substrates by radical-source molecular beam epitaxy (MBE) under the oxygen flow rate of 0.3 sccm, and found that the phase transition takes place at the Cd composition x~0.69 and the largest band gap is ~3.23 eV in RS structure. The oxygen flow rate affects to the growth properties of ZnCdO. Here, we have grown Al-doped ZnCdO thin films on MgO (100) substrate under the oxygen flow rate of 1.0 sccm and found improved optical and electrical properties by increasing oxygen flow rate.
In the previous study, we have grown Al-doped ZnCdO thin films on MgO (100) substrates by radical-source molecular beam epitaxy (MBE) under the oxygen flow rate of 0.3 sccm, and found that the phase transition takes place at the Cd composition x~0.69 and the largest band gap is ~3.23 eV in RS structure. The oxygen flow rate affects to the growth properties of ZnCdO. Here, we have grown Al-doped ZnCdO thin films on MgO (100) substrate under the oxygen flow rate of 1.0 sccm and found improved optical and electrical properties by increasing oxygen flow rate.