High temperature annealing of spin coated Pr1-xCaxMnO3 thim...

Details High temperature annealing of spin coated Pr1-xCaxMnO3 thim... High temperature annealing of spin coated Pr1-xCaxMnO3 thim...

2003-08-13

2004-08-10

Nhu, David (Department: 2818)

Semiconductor device manufacturing: process

Coating of substrate containing semiconductor region or of...

Insulative material deposited upon semiconductive substrate

C438S782000

Reexamination Certificate

active

06774054

ABSTRACT:

FIELD OF THE INVENTION
This invention relates to spin coating of PCMO thin films, and specifically to an annealing process to enhance the bipolar switching properties of PCMO thin films in RRAM applications.
BACKGROUND OF THE INVENTION
Electrically programmable resistance non volatile memory device operated at room temperature that use spin on PCMO thin film on Pt substrate was demonstrated by Zhuang, et al., in U.S. patent application Ser. No. 10/256,380, filed Sep. 26, 2002, for
Method Resistance Memory Metal Oxide Thin Film Deposition
, describes a technique for forming a CMR layer in a RAM device. The PCMO thin film was grown on a Platinum layer, and, following a low heat treatment, exhibited amorphous or polycrystalline structure. This resistor may be reversibly programmed to a high or a low resistance state by unipolar electrical pulses having different pulse widths. However, in order to use the CMR in a RRAM application, bipolar electrical pulses switching properties are more preferred. These switching properties require a well-crystallized PCMO thin film.
SUMMARY OF THE INVENTION
A method of forming a PCMO thin film in a RRAM device includes preparing a substrate; depositing a metal barrier layer on the substrate; forming a bottom electrode on the barrier layer; spin-coating a layer of Pr
1−x
Ca
x
MnO
3
(PCMO) on the bottom electrode using a PCMO precursor consisting of Pr(CH
3
CO
2
)
3
.H
2
O, Ca(CH
3
CO
2
)
2
.H
2
O, and Mn(III)(CH
3
CO
2
)
3
.2H
2
O, in an acetic acid solvent; baking the PCMO thin film in at least one or more separate baking steps, wherein the baking steps may include, e.g., a first baking step at a temperature of between about 50° C. to 150° C. for between about ten seconds to one hour; a second baking step at a temperature of between about 100° C. to 200° C. for between about ten seconds to one hour; and a third baking step at a temperature of between about 150° C. to 300° C. for between about ten seconds to one hour. Alternately, a single baking step at a temperature of between about 50° C. to 300° C. for between about ten seconds to one hour may be used. The baking step(s) are followed by annealing the PCMO thin film in a first annealing step at a temperature of between about 400° C. to 900° C. for between about ten seconds to one hour after each spin-coating step; repeating the spin-coating step, the baking step and the first annealing step until the PCMO thin film has a desired thickness; annealing the PCMO thin film in a second annealing step at a temperature of between about 450° C. to 1000° C., for between about one minute to twenty-four hours, thereby producing a PCMO thin film having a crystalline structure of Pr
1−x
Ca
x
MnO
3
, where 0.2<=X<=0.5; depositing a top electrode; patterning the top electrode; and completing the RRAM device.
It is an object of the invention to specify a high temperature annealing method of a spin-coated PCMO thin film to form a well-crystallized PCMO thin film having bipolar electrical pulse switching properties for use in RRAM applications.
This summary and objectives of the invention are provided to enable quick comprehension of the nature of the invention. A more thorough understanding of the invention may be obtained by reference to the following detailed description of the preferred embodiment of the invention in connection with the drawings.


REFERENCES:
patent: 4946710 (1990-08-01), Miller et al.
patent: 5188902 (1993-02-01), Lin
patent: 5342648 (1994-08-01), MacKenzie et al.
patent: 5656382 (1997-08-01), Nashimoto
patent: 5699035 (1997-12-01), Ito et al.
patent: 6066581 (2000-05-01), Chivukula et al.
patent: 6664117 (2003-12-01), Zhuang et al.

Affiliated with

Also associated with

Rating

High temperature annealing of spin coated Pr1-xCaxMnO3 thim... does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with High temperature annealing of spin coated Pr1-xCaxMnO3 thim..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and High temperature annealing of spin coated Pr1-xCaxMnO3 thim... will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-3340997