A commonly utilized process for patterning structures utilized for integrated circuitry is photolithographic processing. An imagable material (typically photoresist) is provided over a mass which is ultimately to be patterned. Portions of the imagable material are then exposed to radiation, while other portions remain unexposed (in the case of photoresist, the radiation is light). After the exposure, the material is subjected to conditions which selectively remove either the portions of the exposed to radiation, or the portions which were not exposed to radiation. If the imagable material comprises photoresist and the portions exposed to radiation are removed, the photoresist is referred to as a positive photoresist, whereas if the portions which are not exposed to radiation are removed the photoresist is referred to as a negative photoresist. Once the imagable material is patterned, it is utilized as a masking layer for patterning the underlying mass. Specifically, the patterned imagable material covers some portions of the mass, while leaving other portions exposed to an etch which removes the exposed portions. Accordingly, the mass remaining after the etch is in approximately the same pattern as the patterned imagable material formed over the mass.
Photolithographic processing is utilized for patterning numerous materials, including silicon nitride. However, problems can occur during the utilization of photolithographic processing for patterning silicon nitride. Specifically, the pattern formed in silicon nitride is frequently not the same as the pattern which was intended to be formed in the photoresist. Such problem can be particularly severe when utilizing photoresist patterned with deep UV light processing, wherein deep UV light is defined as ultraviolet light having a wavelength of less than or equal to 248 nanometers. It would be desirable to develop methods for avoiding the above-discussed problems.
USPTO Backgrounds
USPTO Backgrounds