HIGH DIELECTRIC CONSTANT METAL OXIDE FILMS VIA PHOTOCHEMICAL METAL ORGANIC DEPOSITION (PMOD™) PROCESS

摘要

The present work describes an emerging methodology for the deposition of directly photopatterned high dielectric constant (k) metal oxide thin films. The methodology, Photochemical Metal Organic Deposition or PMOD™, combines the ease of spin coating and direct photopatterning to overcome limitations encountered with other dielectric patterning methods. The process can be performed at low temperatures ( < 400℃) and does not require the use of plasma etching for pattern definition. This work describes the patterning of photoactive metal-organic titanium precursor films using conventional UV lithographic exposure. Photoconversion of PMOD precursors was studied relative to precursor structure, radiation dose and film thickness. For photoconverted TiO_2 films, residual organic species, refractive index, density, nanoscale porosity and stress were investigated. Also, the effects of post-photoconversion treatments such as annealing and hydrothermal treatment on the removal of residual organic species, densification and crystallization at low temperatures were evaluated. Preliminary electrical measurements were made on photoconverted titania (TiO_2) films.