Low-temperature spin-on-glass method involving high-pressure annealing for filling high-aspect-ratio structures

Abstract

As semiconductor devices are being increasingly scaled down, complex and high-aspect-ratio (AR) structures become necessary. The spin-on-glass (SOG) method has been considered to be effective for filling high-AR (>50) structures, because it enables low-cost fabrication and it has greater amenability to such structures. However, this method requires high temperatures (>600 °C) that can lead to degradation (i.e., oxidation) of adjoining active regions, and additional processes to restore these regions are necessary. We propose a low process temperature (∼400 °C) SOG method involving high-pressure annealing, for the filling of high-AR structures without the creation of voids.