AN ULTRALOW STRESS TA4B ABSORBER FOR X-RAY MASKS

The stress controllability, stress uniformity, stress stability and dr y etching characteristics of Ta4B films deposited by an in-line type s puttering system were investigated in detail. Low average stress Ta4B films within +/-10 MPa have been fabricated on polished SIC films that demonstrate excellent reproducibility by step annealing. Stress unifo rmity of the film showed an approximate range of 7 MPa on a Si wafer i n a 30 mm square area when the deposition conditions were modified. Th e Ta4B him demonstrated long-term stress stability and excellent resis tance to the acid and water used in the cleaning process. The Ta4B fil m also ensures fine pattern formations below 0.2 mu m.