TY - JOUR AU - 안일신 DA - 2008/09 PY - 2008 UR - http://iopscience.iop.org/article/10.1143/JJAP.47.7448/meta UR - https://repository.hanyang.ac.kr/handle/20.500.11754/80664 AB - Resolution enhancement technology (RET) refers to a technique that extends the usable resolution of an imaging system without decreasing the wavelength of light or increasing the numerical aperture (NA) of the imaging tool. Off-axis illumination (OAI) and a phase shift mask (PSM) are essentially accompanied by optical proximity correction (OPC) for semiconductor device manufacturing nowadays. A chromeless PSM is compared with an attenuated PSM (att.PSM) to generate a 45 nm dense line and space pattern. To obtain the best possible resolution, a suitable OPC is required with PSM and the most common application of OPC is the use of bias. An optical system with a high NA, a strong OAI, and a proper polarization can decrease k(1) to a value well below 0.3. A chromeless PSM has various advantages over alternating PSM such as the lack of necessity for double exposure, small pattern displacement, and the lack of critical dimension (CD) error caused by intensity imbalance. However, a chromeless PSM has some disadvantages. In the case of a 100% transmittance pure chromeless PSM, there is no shading material that is usually deposited on the line pattern for both att.PSM and alternating PSM to control linewidth. Because there is no shading material for such a chromeless PSM, the required resist CD has to be obtained using phase only and it is difficult to control the resist CD through pitch. As expected, a chromeless PSM needs a smaller dose than an att.PSM to generate a desired 45 nm CD with a 1.0 NA. Our simulation results show that a 10 nm bias is optimum for chromeless PSMs. We demonstrate that chromeless PSM and att.PSM technology can be used to achieve a 45 nm node with optimum biased OPC. PB - INST PURE APPLIED PHYSICS KW - 45nm line and space KW - chromeless phase lithography (CPL) mask KW - attenuated phase shift mask (att.PSM) KW - optical proximity correction (OPC) KW - bias TI - Optimum Biasing for 45nm Node Chromeless and Attenuated Phase Shift Mask DO - 10.1143/JAPP.47.7448 T2 - JAPANESE JOURNAL OF APPLIED PHYSICS ER -