Semiconductor device manufacturing: process – Making field effect device having pair of active regions... – Having insulated gate
Reexamination Certificate
2000-12-19
2003-02-25
Niebling, John F. (Department: 2812)
Semiconductor device manufacturing: process
Making field effect device having pair of active regions...
Having insulated gate
C438S591000
Reexamination Certificate
active
06524918
ABSTRACT:
FIELD OF THE INVENTION
The present invention relates to a semiconductor device; and, more particularly, to a method for manufacturing a gate structure incorporated therein aluminum oxide (Al
2
O
3
) as a gate dielectric.
DESCRIPTION OF THE PRIOR ART
As is well known, a semiconductor device has been down-sized by a scale down of a design rule. Therefore, a gate oxide tends to rapidly approach 30 Å in thickness and below to increase the capacitance between a gate electrode and a channel region. However, the use of silicon dioxide as a gate dielectric is limited at this thickness and below. Once silicon dioxide (SiO
2
) is formed to a thickness of less than 30 Å, direct tunneling may occur through the gate dielectric to the channel region, thereby increasing a leakage current associated with the gate electrode and the channel region, causing an increase in power consumption.
Since reducing the thickness of the gate dielectric inherently increases the gate-to-channel leakage current, alternative methods have been developed to reduce this leakage current while maintaining thin SiO
2
equivalent thickness. One of these methods is to use a high K dielectric material such as tantalum oxide (Ta
2
O
5
) as the gate dielectric materials to increase the capacitance between the gate and the channel.
However, if a poly-silicon is utilized as a gate electrode, the use of Ta
2
O
5
for gate dielectric materials has a disadvantage in integrating the semiconductor device. That is, an undesired SiO
2
is formed at an interface between Ta
2
O
5
and the poly-silicon, which, in turn, increases an equivalent oxide thickness. In order to overcome this problem, a barrier metal such as titanium nitride (TiN) is employed. However, the TiN makes a threshold voltage shift changed.
Therefore, there is still a demand for developing a high K dielectric as a gate oxide with excellent leakage current as well as a low interface state with both a gate electrode and a silicon substrate.
SUMMARY OF THE INVENTION
It is, therefore, an object of the present invention to provide a method for manufacturing a gate structure incorporated therein aluminum oxide as a gate oxide for use in a semiconductor device.
In accordance with one aspect of the present invention, there is provided a method for manufacturing a gate structure for use in a semiconductor device, the method comprising the steps of: a) preparing a semiconductor substrate provided with an isolation region formed therein; b) forming an aluminum oxide layer (Al
2
O
3
) on the semiconductor substrate; c) carrying out a Si+ plasma doping on the Al
2
O
3
layer; d) annealing the Al
2
O
3
layer doped with the silicon ions; e) forming a conductive layer on top of the Al
2
O
3
layer; and f) patterning the conductive layer, thereby obtaining the gate structure.
REFERENCES:
patent: 3649884 (1972-03-01), Haneta
patent: 3735482 (1973-05-01), Norris et al.
patent: 3853496 (1974-12-01), Kim
patent: 3900352 (1975-08-01), Potter
patent: 4297782 (1981-11-01), Ito
patent: 4906328 (1990-03-01), Freeman et al.
patent: 5561072 (1996-10-01), Saito
patent: 6087615 (2000-06-01), Schork et al.
patent: 6159874 (2000-12-01), Tews et al.
patent: 6235572 (2001-05-01), Kunitomo et al.
patent: 6287965 (2001-09-01), Kang et al.
Jang Se-Aug
Lee Jeong-Youb
Park Dae-Gyu
Finnegan Henderson Farabow Garrett & Dunner L.L.P.
Hyundai Electronics Industries Co,. Ltd.
Niebling John F.
Roman Angel
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