SEMICONDUCTOR PROCESSING

The production of nextgeneration 256Mbit DRAM (dynamic randomaccess memory) chips with optical lithography will require writing feature sizes of less than 0.5 µm. Researchers at Rice University (Houston, TX) and Texas Instruments (Stafford, TX) developed an interferometric phaseshifting method that uses a singlelayer chromium mask to record patterns in UV photoresist. This method offers significant resolution and contrast enhancement over conventional trans mission photolithography processes