Acute competitive pressures to produce ever faster and more complex integrated circuits at diminishing costs continually drive IC manufacturers to find new, improved materials and processes without investing in new equipment sets. Currently in the microelectronic industry, most equipment sets utilize deep ultraviolet (DUV) lasers in photolithography. One promising avenue to meet this demand for lower cost of ownership in DUV photolithography is the development of new materials to use as wet developable DUV bottom antireflective coatings (BARCs). BARCs are necessary to control reflections of light from the substrate surface when the photoresist is exposed to light. Traditional BARC technology requires a four-step process including an additional etch step to remove the BARC. In contrast, photolithography with a wet developable BARC requires only three steps because the BARC is removed concurrently with the photoresist. This will not only reduce cost, but also increase manufacturing throughput because fewer production steps will be required. This new material will meet industry requirements such as low reflectivity, spin bowl compatibility, photoresist compatibility, and patternability. These characteristics will allow easy integration of wet developable DUV BARCs into current equipment sets without further investment. Anticipated Benefits/Commercial Applications: A wet developable, DUV BARC will greatly reduce the cost of ownership in photolithography. Anticipated savings will amount to a minimum of $ 400,000, annually, for a modern IC fab. Wet developable material will solve many problems observed with dry etch BARCs, including loss of resist material and possible contamination of the profile. This is because wet developable BARCs do not require etching for their removal. The commercial applications of a wet developable BARC include, potentially, any application that requires a BARC. This includes numerous stages of integrated circuit manufacturing where photolithography is used and reflection of light must be controlled.
Keywords: BARC, Wet Developable, DUV, antireflective coating
