Self assembly in semiconductor microelectronics: Self-aligned sub-lithographic patterning using diblock copolymer thin films

Self-assembling diblock copolymer thin films are an intriguing possible photolithography alternative for high-resolution patterning of advanced integrated circuit device elements. Cylindrical- and lamellar-phase materials spontaneously form patterns suggestive of contact-hole arrays and transistor gates at critical dimensions below 20nm. Besides high resolution, any serious lithographic process requires a means of pattern registration, and we discuss our efforts to develop self-aligned self assembly techniques using diblock copolymer materials. We describe the critical role of polymer surface interactions in affecting self-assembled pattern orientations. Control and design of surface properties allow precise registration of sub-20nm polymer domains to larger-scale lithographic layers.