Recent Trends on the ALD Technology for ULSI Device Fabrication

Abstract

Since Al2O3 film by Atomic Layer Deposition (ALD) has successfully been introduced as a capacitor dielectric for DRAM, now it is widely used up to the device of 100nm design rule. At the design rule of 100nm or below, various thin films, such as high k dielectrics for capacitor or gate oxide, metal electrodes for the dielectrics, and diffusion barrier for contact or interconnection are highly required to be developed using ALD technique to overcome various challenges caused by rapid device shrinkage. Thus, ALD technique is now essential for ULSI device fabrication due to its unique features such as excellent step coverage, high quality film structure having low defect density, lower deposition temperature, and precision composition control of multi- component oxide. In this paper, several important technical points of ALD process for ULSI applications were described and discussed with several recent experimental data