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In this work, by controlling the oxygen flow rate (OFR) (from 0% to 30%), we suggest using a p-type copper aluminum oxide (p-CuAlO2) interlayer to enhance the high breakdown and low leakage current for β-Ga2O3-based power device applications. Results of AFM measurements on p-CuAlO2 films performed using various OFRs demonstrate that greater OFRs result in an increase in film roughness payable to the unavoidable leading of defects/oxygen vacancy (VO). We used XPS and TEM analysis to validate the surface elemental compositions, chemical states, band offsets and microstructural properties of p-CuAlO2/β-Ga2O3 heterojunction (HJ) with different OFRs. With increasing OFR from 0% to 17.6%, the VBO and CBO values of HJ were decreased from 1.73 eV to 1.23 eV and from 0.53 eV to 0.38 eV respectively. Then, with increasing OFR from 17.6% to 30%, VBO was decreased from 1.23 eV to 1.13 eV while CBO increased from 0.38 eV to 0.58 eV. The staggered-gap (type-II) across the p-CuAlO2/β-Ga2O3 HJ is identified the entire OFRs. The rising tendency of optical bandgap (Eg) of p-CuAlO2 with range of OFRs, a maximum Eg of 4.35 eV was obtained with OFR of 30%. Furthermore, the electrical and carrier transport properties of p-CuAlO2/β-Ga2O3 HJ were studied using I–V and C–V techniques. The reverse breakdown voltage (Vbr) of HJ is strongly dependent on OFRs. With increasing OFRs, Vbr was decreased from 937 V to 924 V, and then to 1000 V with increasing OFR from 0% to 17.6% and then to 30%. In addition, a decrease in the interface state density (NSS) with increasing OFRs was observed which indicates that oxygen may be an effective surface passivation. Analysis confirmed that Poole-Frenkel emission dominates the reverse leakage current of all the HJ samples. The type-II p-CuAlO2/β-Ga2O3 HJ may facilitate the design and manufacture of high-performance β-Ga2O3-based heterojunctions and advance optoelectronic devices.

Today, intellectual education based on the various experiences and emotions of citizens through culture and art education draws attention in terms of obtaining improvements in social welfare. Citizens can become further aware of culture and art and get a wider range of benefits in cultural welfare. Culture and art education are important activities of cultural welfare. This study examines some of the successes of the Seoul Arts Center academy, which represents and hosts diverse cultural and art activities in South Korea. These activities have led to successful promotion of culture and art education for Seoul citizens. Based on Lewin’s change management process model, the cases that were analyzed focus on the change in culture and art education in the Seoul Arts Center academy. Findings from this study indicate the contribution to the improvement in cultural welfare for citizens from their engagement in activities within art education and culture. The discussion also highlights that good management of the changes in educational activity with the citizens’ needs and improvements in the maturity of civil society were critical factors for educational sustainability and success.