Method for growing thin films

Details Method for growing thin films Method for growing thin films

2001-10-25

2004-06-01

Chen, Bret (Department: 1762)

Coating processes

Coating by vapor, gas, or smoke

Mixture of vapors or gases utilized

C427S374100

Reexamination Certificate

active

06743474

ABSTRACT:

FIELD OF THE INVENTION
The present invention relates generally to the creation of thin layers. More specifically, the invention relates to the creation of a plurality of monolayers.
BACKGROUND OF THE INVENTION
Atomic layer epitaxy (ALE) has become widely adopted as a method of providing atomic layer deposition and very thin film creation. The basic concept is a sequential exposure of a suitable surface to a precursor species followed by a co-reactant species. Originally, fluxes of two elements were alternated. Later, alternating molecular precursors were employed, which allowed expansion to several different co-reactant species. In both cases, reactants (elements and molecular precursors) are chemisorbed at each layer of creation. This resulted in self-limiting chemistry. Approaches with molecular precursors use reactants that are volatile, such as SiCl
4
and H
2
O or where at least one co-reactant is in a gaseous state.
ALE may be considered a variant of the more general method of molecular beam epitaxy (MBE), where a thin film deposition process is controlled by flux intensity, time exposure, and temperature. Molecular beam epitaxy may be done in clusters, which may make control of the number of layers difficult. Atomic layer epitaxy may allow a layer-by-layer deposition, which may provide control over the number of layers deposited. Such molecular beam epitaxy does not always require chemisorption, but may instead use physisorption.
In semiconductor processing, barrier layers may be used to separate one material from another. For example, it may be desirable to use a barrier layer to separate a copper conductor layer from a silicon layer. Such barrier layers must be thick enough to provide complete separation, but thin enough to allow a more compact chip. To provide a barrier layer that is less than 100 nanometers instead of hundreds of nanometers, and provides complete separation is desirable. Present techniques for creating barrier layers, such as sputtering, chemical vapor deposition, and plasma enhanced chemical vapor deposition are normally used to create barrier layers that are hundreds of nanometers thick. Such barriers have a porosity that may require a thick layer. In addition, contaminants in the barrier layer may make the barrier layer less effective.
It would be desirable to create thin layers by an atomic layer deposition process that is an alternative to molecular beam epitaxy and atomic layer epitaxy. It would be desirable to create thin layers that have a high purity and low porosity, which may be more effective as barrier layers.
SUMMARY OF THE INVENTION
To achieve the foregoing and other objects and in accordance with the purpose of the present invention, a method of forming a layer over a substrate is provided. Generally, a layer of a first reactive species is deposited over the substrate. The layer of the first reactive species is reacted with a second reactive species to create a first product. Unreacted reactive species is preferentially desorbed, leaving a layer of the first product.
In addition, a thin film of a plurality of layers over a substrate is provided where each layer is formed by a method. Generally, a layer of a first reactive species is deposited over the substrate. The layer of the first reactive species is reacted with a second reactive species to create a first product. Unreacted reactive species is preferentially desorbed, leaving a layer of the first product.
These and other features of the present invention will be described in more detail below in the detailed description of the invention and in conjunction with the following figures.


REFERENCES:
patent: 5255067 (1993-10-01), Carrabba et al.
patent: 5746826 (1998-05-01), Hasegawa et al.
patent: 6464779 (2002-10-01), Powell et al.
patent: 6482740 (2002-11-01), Soininen et al.

Affiliated with

Also associated with

Rating

Method for growing thin films does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Method for growing thin films, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Method for growing thin films will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-3348364