Atomic layer-by-layer MOCVD of complex metal oxides and in situ process monitoring

The progress of atomic layer-by-layer metal-organic (MO) CVD of complex met al oxides and related growth technologies is reviewed. Atomic layer-by-laye r MOCVD produces thin films of complex metal oxides that are of high crysta lline quality, with a very smooth surface. These features allow us to fabri cate modulated structures on an atomic scale, such as delta -doping, superl attice structure, and heterostructures. A common problem of oxide MOCVD is poor controllability of the growth conditions, mainly caused by instability of precursor supply. To overcome this problem, new precursors have been de veloped, and in situ process monitoring, using an ultrasonic transducer and spectroscopic ellipsometry, is applied during the MOCVD process. The repro ducibility of MOCVD growth has been improved significantly.