Technique for producing small islands of silicon on insulator
Patent 6174784 Issued on January 16, 2001. Estimated Expiration Date: November 14, 2017. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.
438/405, And separate partially isolated semiconductor regions257/E21.554, Using auxiliary pillars in recessed region, e.g., to form LOCOS over extended areas (EPO)257/E21.561, Using semiconductor or insulator technology, i.e., SOI technology (EPO)257/E21.564, SOI together with lateral isolation, e.g., using local oxidation of silicon, or dielectric or polycrystalline material refilled trench or air gap isolation regions, e.g., completely isolated semiconductor islands (EPO)438/404, Total dielectric isolation438/410, Encroachment of separate locally oxidized regions438/425Combined with formation of recessed oxide by localized oxidation
Using sub-micron technology, silicon on insulator (SOI) rows and islands are formed in a silicon substrate. Trenches are directionally-etched in the silicon substrate, leaving rows of silicon between the trenches. Silicon nitride is then deposited over the trenches, extending partly down the sides of the trenches. An isotropic chemical etch is then used to partially undercut narrow rows of silicon in the substrate. A subsequent oxidation step fully undercuts the rows of silicon, isolating the silicon rows from adjacent active areas. Devices, such as transistors for CMOS and DRAMs, are then formed in active areas, wherein the active areas are defined on the silicon rows by LOCal Oxidation of Silicon (LOCOS).
Other References
Abe, et al., "Silicon Wafer-Bonding Process Technology for SOI Structures", Conference on Solid State Devices and Materials, Sponsored by The Japan Society of Applied Physics, 853-856, (1990)
Auberton-Herve, A.J., "SOI: Materials to Systems", Digest of the International Electron Device Meeting, San Francisco, 3-10, (Dec. 1996)
Cartagena, et al., "Bonded Etchback Silicon on Sapphire Bipolar Junction Transistors", In: The Electrochemical Society Interface, 2(1), Program and Abstracts: 183rd Meeting of the Electrochemical Society Pennington, NJ, 2 pages, (1993)
Eaton, W.P., et al., "Wafer Bonding by Low Temperature Melting Glass", Proceedings of the First International Symposium on Semiconductor Wafer Bonding, Gosele, U., et al., (eds.), Electrochemical Society, Pennington, NJ, 146-152, (1992)
Harendt, et al., "Silicon on Insulator Material by Wafer Bonding", Journal of Electronic Materials, 20(3), 267-77, (Mar. 1991)
Horiuchi, M., et al., "A Mechanism of Silicon Wafer Bonding", Proceedings of the First International Symposium on Semiconductor Wafer Bonding, 48-62, (1992)
Imthurn, et al., "Bonded Silicon-on-Sapphire Wafers and Devices", Journal of Applied Physics, 72(6), 2526-7, (Sep. 1992)
Lee, B.H., et al., "Novel Pattern Transfer Process for Bonded SOI Giga-bit DRAMs", IEEE International SOI Conference, Piscataway, NJ, 114-115, (1996)
Lu, D., et al., "Bonding Silicon Wafers by Use of Electrostatic Fields Followed by Rapid Thermal Heating", Materials Letters, 4(11), 461-464, (Oct. 1986)
Mumola, P.B., et al., "Recent Advances in Thinning of Bonded SOI Wafers by Plasma Assisted Chemical Etching", Electrochemical Society Proceedings, 95-7, 28-32, (1995)
Nakamura, et al., "Giga-bit DRAM Cells with Low Capacitance and Low Resistance Bit-Lines on Buried MOSFET's and Capacitors by Using Bonded SOI Technology-Reversed-Stacked--Capacitor (RSTC) Cell--", Technical Digest--International Electron Devices Meeting, 889-892, (1995)
Quenzer, H.J. et al., "Low Temperature Silicon Wafer Bonding for Micromechanical Applications", Proceedings of the First International Symposium on Semiconductor Wafer Bonding, Gosele, U., et al., (eds.), Electrochemical Society, Pennington, NJ, 92-100, (1992)
Huang, W.L., et al., "TFSOI Complementary BiCMOS Technology for Low Power Applications", IEEE Transactions on Electron Devices, 42, 506-512, (Mar. 1995)
Kuge, S., et al., "SOI-DRAM Circuit Technologies for Low Power High Speed Multigiga Scale Memories", IEEE Journal of Solid-State Circuits, 31, 586-591, (Apr. 1996