CAJ | 학술논문

将以极化为特征、具有丰富功能特性的介电氧化物材料通过外延薄膜的方式，在半导体GaN上制备介电氧化物／GaN集成薄膜，其多功能一体化与界面耦合效应可推动电子系统单片集成化的进一步发展。然而，由于2类材料物理、化学性质的巨大差异，在GaN上生长介电薄膜会出现严重的相容性生长问题。采用激光分子束外延技术（LMBE），通过弹性应变的TiO2的缓冲层来减小晶格失配度，降低介电薄膜生长温度，控制界面应变释放而产生的失配位错，提高了介电薄膜外延质量；通过低温外延生长MgO阻挡层，形成稳定的氧化物／GaN界面，阻挡后续高温生长产生的扩散反应；最终采用TiO2／MgO组合缓冲层控制介电／GaN集成薄膜生长取向、界面扩散，降低集成薄膜的界面态密度，保护GaN半导体材料的性能。所建立的界面可控的相容性生长方法，为相关集成器件的研发提供了一条可行的新途径。
장이겁화위특정、구유봉부공능특성적개전양화물재료통과외연박막적방식，재반도체GaN상제비개전양화물／GaN집성박막，기다공능일체화여계면우합효응가추동전자계통단편집성화적진일보발전。연이，유우2류재료물리、화학성질적거대차이，재GaN상생장개전박막회출현엄중적상용성생장문제。채용격광분자속외연기술（LMBE），통과탄성응변적TiO2적완충층래감소정격실배도，강저개전박막생장온도，공제계면응변석방이산생적실배위착，제고료개전박막외연질량；통과저온외연생장MgO조당층，형성은정적양화물／GaN계면，조당후속고온생장산생적확산반응；최종채용TiO2／MgO조합완충층공제개전／GaN집성박막생장취향、계면확산，강저집성박막적계면태밀도，보호GaN반도체재료적성능。소건립적계면가공적상용성생장방법，위상관집성기건적연발제공료일조가행적신도경。
The integration of multifunctional oxide dielectrics possessing spontaneous polarization with GaN semiconductors can put forward a new direction of developing electronic devices with higher performances. However, dielectric oxides and CaN semiconductors are quite different from each other. It will cause many problems when the two kinds of materials are integrated together. Laser molecular beam epitaxy （LMBE） was used to realize epitaxial growth of dielectric films on GaN substrates. TiO2 template layer was inserted between SrTiO3 dielectric film and GaN to reduce lattice mismatch. It was found that the growth temperature of SrTiO3 films was decreased by 200 ℃ due to similar Ti-O6 octahedron structure between TiO2 and STO. In addition, it was found that the strong ionic characteristics of MgO can lead to the remarkable reduction of the interface diffusion between oxide and GaN. Thus TiOJMgO combined buffer layer was used to realize compatible integrated growth of dielectric/GaN structures which can preserve the semiconductor surface and induce dielectric film epitaxial growth. This new method can provide a practical technique to develop new devices containing dielectrics and GaN.