Optical in situ monitoring of plasma-enhanced atomic layer deposition process

Research paper by Muhammad Zeeshan Arshad, Kyung Jae Jo, Hyun Gi Kim Sang Jeen Hong

Indexed on: 01 Jun '18Published on: 28 May '18Published in: Japanese journal of applied physics (2008)


An optical in situ process monitoring method for the early detection of anomalies in plasma process equipment is presented. Cyclic process steps of precursor treatment and plasma reaction for the deposition of an angstrom-scale film increase their complexity to ensure the process quality. However, a small deviation in process parameters, for instance, gas flow rate, process temperature, or RF power, may jeopardize the deposited film quality. As a test vehicle for the process monitoring, we have investigated the aluminum-oxide (Al 2 O 3 ) encapsulation process in plasma-enhanced atomic layer deposition (PEALD) to form a moisture and oxygen diffusion barrier in organic-light emitting diodes (OLEDs). By optical in situ monitoring, we successfully identified the reduction in oxygen flow rates in the reaction steps, which resulted in a 2.67 times increase in the water vapor transmission ratio (WVTR) of the deposited Al 2 O 3 films. Therefore, we a...