|(3 of 43)|
|United States Patent||6,117,619|
|Forbes, et. al.||Sept. 12, 2000|
An antireflective coating (ARC) or antireflective layer (ARL) is interposed between a photoresist layer and an underlying substrate. The ARC includes an optically absorptive polysilicon germanium or polysilicon first layer, deposited by low pressure chemical vapor deposition (LPCVD). An optically transmissive second layer is grown on the first layer by oxidizing it at low temperature. The low temperature oxidation accurately controls the thickness, and optical impedance, of the second layer. The optical impedances of the second and photoresist layers are matched for minimizing reflections and reducing photolithographic limitations such as swing effect and reflective notching. The low temperature oxidation is compatible with low thermal budget layers (e.g., aluminum or other metals), which are typically highly reflective at ultraviolet (UV) and deep ultraviolet (DUV) lithographic exposure wavelengths.
|Inventors:||Forbes; Leonard (Corvallis, OR); Ahn; Kie Y. (Chappaqua, NY).|
|Assignee:||Micron Technology, Inc. (Boise, ID).|
|Filed:||Jan. 5, 1998|
|Intl. Cl. :||G03C 5/00|
|Current U.S. Cl.:||430/313; 430/311; 430/327; 430/950|
|Field of Search:||430/311, 313, 327, 950|
Cirelli, R., et al., "A Multilayer Inorganic Antireflective System for use in 248 nm Deep Ultraviolet Lithography", J. Vac. Sci. Technol. B, 14, 4229-4233, (Nov./Dec. 1996).
Dammel, R.R., et al., "Modeling of Bottom Anti-Reflection Layers: Sensitivity to Optical Constants (Photolithography)", Pro. SPIE, vol. 2724, 754-69, (1996).
Dijkstra, et al., "Optimization of Anti-Reflection Layers for Deep UV Lithography", SPIE Optical/Laser Microlithography VI, vol. 1927, 275-86, (1993).
Hurley, P., et al., "Low Temperature Plasma Oxidation of Polycrystalline Silicon", Pro. 7th European Conf. on Insulating Films on Semiconductors: Contributed Papers, Section 5, IOP Publishing Ltd., 235-238, (1991).
King, T., et al., "Deposition and Properties of Low-Pressure Chemical-Vapor Deposited Polycrystalline Silicon-Germanium Films", J. Electrochemical Society, 141, 2235-2241, (Aug. 1994).
Li, P., et al., "Formation of Stoichiometric SiGe Oxide by Electron Cyclotron Resonance Plasma", Appl. Phys. Lett, 60, 3265-3267, (Jun. 1992).
Mohajerzadeh, S., et al., "A Low-Temperature Ion Vapor Deposition Technique for Silicon and Silicon-Germanium Epitaxy", Canadian J. Physics, 74, S69-S73, (1996).
Mohri, M., et al., "Effect of SiF(4)/SiH(4)/H (2) Flow Rates on Film Properties of Low-Temperature Polycrystalline Silicon Films Prepared by Plasma Enhanced Chemical Vapor Deposition", IEICE Transactions on Electronics, E77-C, 1677-1684, (Oct. 1994).
Mukhopadhyay, M., et al., "Properties of SiGe Oxides Grown in a Microwave Oxygen Plasma", J. Applied Physics, 78, 6135-6140, (Nov. 1995).
Ogawa, T., et al., "Advantages of a SiOxNy:H Anti-Reflective Layer for ArF Excimer Laser Lithography", Japanese J. Applied Physics, 35, 6360-6365, (1996).
|(3 of 43)|