Methods providing oxide layers having reduced thicknesses at central portions thereof

摘要

Methods of forming an integrated circuit device may include forming first and second spaced apart source/drain regions on a surface of a semiconductor substrate. A gate insulating layer can be formed on the semiconductor substrate extending between the first and second spaced apart souce/drain regions. The gate insulating layer can have a reduced thickness at a central portion thereof between the first and second spaced apart source/drain regions. A thickness of the gate insulating layer can increase as it extends toward each of the source/drain regions. A gate electrode can be formed on the gate insulating layer such that the gate insulating layer is between the semiconductor substrate and the gate electrode. Related devices are also discussed.