Exposure control for phase shifting photolithographic masks

A method for manufacturing an integrated circuit, comprising:

• forming a layer of resist on a wafer;
• exposing the layer to a first dose of radiation through a phase shifting pattern in a first mask, the first dose of radiation characterized by changeable parameters having values selected for exposure of the phase shifting pattern;
• and
• exposing the layer to a second dose of radiation through a trim pattern in a second mask protecting a pattern defined using the phase shifting pattern and clearing phase shifting artifacts, the second dose of radiation characterized by said changeable parameters having substantially the same values as the changeable parameters selected for exposure of the phase shifting pattern with the first dose of radiation, wherein substantially the same values comprises within plus or minus 10%.

A method for manufacturing an integrated circuit, comprising:

• forming a layer of resist on a wafer in a first process station;
• moving the wafer to a second process station including a radiation source, a mask and an optical path for exposing the wafer to radiation, the optical path being characterized by optical parameters;
• exposing, in the second process station, the layer to a first dose of radiation through a phase shifting pattern in said mask using a first setting of changeable values for the optical parameters;
• and
• exposing, in the second process station, the layer to a second dose of radiation through a trim pattern in said mask using said first setting of changeable values, said trim pattern protecting a pattern defined using the phase shifting pattern and clearing phase shifting artifacts.