Electrical breakdown of rare earth oxide insulator thin films in silicon MIS structures

摘要

The rare earth oxides (REO) have emerged as important insulating materials. Thin insulating films are used in a wide variety of components in optical and electronic devices. Thin films of REO exhibit good dielectric properties, thermal and chemical stability. The electrical resistivity of the films is of the order of 10/sup 14/-10/sup 16/ /spl Omega/ cm and the dielectric constant is in the range of 12-13. Knowledge of the breakdown mechanism can be important for the design of thin film capacitors, varactors, transistors and switching elements with memory. In the present report we discuss the results of the dielectric breakdown study of thin Sm/sub 2/O/sub 3/, Lu/sub 2/O/sub 3/ and Y/sub 2/O/sub 3/ films and propose a model of this process in accordance with which the breakdown process is realized by means of the critical charge accumulation and the corresponding strengthening of the electrical field in the insulator.