Methods are provided for forming integrated circuit devices. A spin on glass (SOG) insulating layer is formed on an integrated circuit substrate. The SOG insulating layer includes sidewalls that define contact holes therein and spacers are formed on the sidewalls of the SOG insulating layer. Integrated circuit devices are also provided. The integrated circuit devices include an integrated circuit substrate, a spin on glass (SOG) insulating layer on the integrated circuit substrate. The SOG insulating layer includes sidewalls that define contact holes therein and spacers are provided on sidewalls of the SOG insulating layer.