Berger, L.L.BergerDress, P.P.DressYang, S.-H.S.-H.YangKuo, C.-H.C.-H.Kuo2022-03-102022-03-102007https://publica.fraunhofer.de/handle/publica/35641810.1117/12.728926The demand for ever smaller features in integrated circuit manufg. continues to put more stringent requirements on photomask fabrication, particularly with respect to crit. dimension (CD) control. A high resoln. process for making attenuated-phase-shift masks (attPSM) for the 45nm node with a neg.-tone chem. amplified resist (nCAR), utilizing a new precision bake system, was evaluated. This process showed a significant performance improvement in crit. dimension uniformity (CDU), resp. to an established process based on an APB5500 system. A CD-uniformity improvement from 2.1nm CD 3s to 1.3nm CD 3s (40%) was achieved on a demanding layout. The new precision bake system utilizes an improved multi-zone hotplate design and control algorithm, which enables highly precise temp. controllability, facilitating a superior temp. ramp-up performance, as well as significantly improved temp. setpoint stability, as has been measured with a 25-point sensor mask for a 95 DegC bake process. The new precision bake system shall now be introduced to the market within the HamaTech MaskTrack series.en620conference paper