United States Patent 6,049,106

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United States Patent	6,049,106
Forbes	Apr. 11, 2000

Large grain single crystal vertical thin film polysilicon MOSFETs

Abstract

A vertical thin film transistor formed in a single grain of polysilicon having few or no grain boundaries for use in memory, logic and display applications. The transistor is formed from a thin film of polysilicon having large columnar grains, in which source and drain regions have been formed. The large grain size and columnar grain orientation of the thin film are provided by recrystallizing a thin amorphous silicon film, or by specialized deposition of the thin film. Use of a thin film permits the transistor to be formed on an insulating substrate such as glass, quartz, or inexpensive silicon rather than a semiconductor chip, thereby significantly decreasing device cost.

Inventors:	*Forbes*; Leonard (Corvallis, OR).
Assignee:	*Micron* Technology, Inc. (Boise, ID).
Appl. No.:	229,891
Filed:	Jan. 14, 1999

Intl. Cl. :	H01L 29/72
Current U.S. Cl.:	257/329; 257/49; 257/51; 257/64; 257/67
Field of Search:	257/329, 49, 51, 64, 67

References Cited | [Referenced By]

U.S. Patent Documents

5,315,140	May, 1994	Sugahara et al.
5,382,549	Jan., 1995	Ohshima et al.
5,385,863	Jan., 1995	Tatsumi et al.
5,491,107	Feb., 1996	Turner et al.
5,773,358	Jun., 1998	Wu et al.
5,792,700	Aug., 1998	Turner et al.	257/329
5,847,406	Dec., 1998	Dennison et al.	257/329
5,872,374	Feb., 1999	Tang et al.	257/329

Other References

G.K. Giust et al., "Laser Recrystallization of Polycrystalline Silicon in Recessed Structures", Journal of Electronic Materials, vol. 26, No. 8, 1997, pp. L13-L16.

Do-Hyun Choi et al., "Electrical Properties of Ultralarge Grain Polycrystalline Silicon Film Produced by Excimer-Laser Recrystallization Method", Jpn. J. Appl. Phys. vol. 34 (1995) pp. 459-463.

E. Srinivasan et al., "Large Crystallite Polysilicon Deposited Using Pulsed-Gas PECVD at Temperatures Less than 250 deg. C", Mat. Res. Soc. Symp.. Proc. vol. 452, 1997, Materials Research Society, pp. 989-994.

Eun Gu Lee et al., A Study of the Morphology and Microstructure of LPCVD Polysilicon, Journal of Materials Science 28 (1993) pp. 6279-6284.

Primary Examiner: Wojciechowicz; Edward
Attorney, Agent or Firm: Dickstein Shapiro Morin & Oshinsky LLP
38 Claims, 11 Drawing Figures


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