Haze-free BST films

Semiconductor device manufacturing: process – Making field effect device having pair of active regions... – Having insulated gate

Reexamination Certificate

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C257S306000

Reexamination Certificate

active

06852593

ABSTRACT:
Described herein is a method for producing a haze-free (Ba, Sr)TiO3(BST) film, and devices incorporating the same. In one embodiment, the BST film is made haze-free by depositing the film with a substantially uniform desired crystal orientation, for example, (100), preferably by forming the film by metal-organic chemical vapor deposition at a temperature greater than about 580° C. at a rate of less than about 80 Å/min, to result in a film having about 50 to 53.5 atomic percent titanium. In another embodiment, where the BST film serves as a capacitor for a DRAM memory cell, a desired {100} orientation is induced by depositing the bottom electrode over a nucleation layer of NiO, which gives the bottom electrode a preferential {100} orientation. BST is then grown over the {100} oriented bottom electrode also with a {100} orientation. A nucleation layer of materials such as Ti, Nb and Mn can also be provided over the bottom electrode and beneath the BST film to induce smooth, haze-free BST growth. Haze-free BST film can also be favored by forming the bottom electrode at high temperatures close to those used for BST deposition, and without a vacuum break between the bottom electrode and BST deposition.

REFERENCES:
patent: 5185689 (1993-02-01), Maniar
patent: 5335138 (1994-08-01), Sandhu et al.
patent: 5406445 (1995-04-01), Fujii et al.
patent: 5506166 (1996-04-01), Sandhu et al.
patent: 5581436 (1996-12-01), Summerfelt et al.
patent: 5717234 (1998-02-01), Si et al.
patent: 5781404 (1998-07-01), Summerfelt et al.
patent: 5783253 (1998-07-01), Roh
patent: 5822175 (1998-10-01), Azuma
patent: 5889299 (1999-03-01), Abe et al.
patent: 5973911 (1999-10-01), Nishioka
patent: 6010931 (2000-01-01), Sun et al.
patent: 6117482 (2000-09-01), Kawahara et al.
patent: 6136639 (2000-10-01), Seon
patent: 6238966 (2001-05-01), Ueda et al.
patent: 6277436 (2001-08-01), Stauf et al.
patent: 6285051 (2001-09-01), Ueda et al.
patent: 6319764 (2001-11-01), Basceri et al.
patent: 6339527 (2002-01-01), Farooq et al.
patent: 6660535 (2003-12-01), Basceri et al.
patent: 0 617 439 (1994-03-01), None
patent: WO 9525340 (1995-09-01), None
patent: 406333772 (1994-12-01), None
Joo, “Fabrication and Characterization of MOCVD (Ba, Sr)TiO3 Thin Films for High Density Capacitors”, Proceeding of 1997 5th International Conference an VLSI and CAD, The Secretariat of ICVC '97, 1997.
Hiromi Itoh et al.,“Integration of BST Thin Film for Dram Fabrication”,Integrated Ferroelectrics, 1995 vol. 11, pp. 101-109.
C. Basceri,“An Important Failure Mechanism in MOCVD (Ba,Sr)TiO3Thin Films: Resistance Degradation”,Ferroelectric Thin Films IV, Materials Research Society, Symposium Proceedings vol. 493, 1998, pp. 9-14.
Chung Ming Chu and Pang Lin,“Electric Properties and Crystal Structure of a (Ba,Sr)TiO3Films Prepared at Low Temperatures on a LaNiO3Electrode by Radio-Frequency Magnetron Sputtering”,Appl. Phys. Lett., vol. 70 (2), Jan. 13, 1997, pp. 249-251.

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