Depth-resolved subsurface defects in chemically etched SrTiO3

作者：Zhang Jun^*; Doutt D; Merz T; Chakhalian J; Kareev M; Liu J; Brillson L J

来源：Applied Physics Letters, 2009, 94(9): 092904.

DOI：10.1063/1.3093671

• annealing
• cathodoluminescence
• etching
• strontium compounds
• surface structure
• vacancies (crystal)

Depth-resolved cathodoluminescence spectroscopy of atomically flat TiO2-terminated SrTiO3 single crystal surfaces reveals dramatic differences in native point defects produced by conventional etching with buffered HF (BHF) and an alternative procedure using HCl-HNO3 acidic solution (HCLNO), which produces three times fewer oxygen vacancies before and nearly an order of magnitude fewer after pure oxygen annealing. BHF-produced defect densities extend hundreds of nanometers below the surface, whereas the lower HCLNO-treated densities extend less than 50 nm. This "Arkansas" HCLNO etch and anneal method avoids HF handling and provides high-quality SrTiO3 surfaces with low native defect density for complex oxide heterostructure growth.

• 出版日期2009-3-2