Adhesive bonding and miscellaneous chemical manufacture – Differential fluid etching apparatus – With microwave gas energizing means
Reexamination Certificate
1999-06-29
2001-04-10
Mills, Gregory (Department: 1763)
Adhesive bonding and miscellaneous chemical manufacture
Differential fluid etching apparatus
With microwave gas energizing means
C118S7230IR, C204S298080, C204S298340
Reexamination Certificate
active
06214162
ABSTRACT:
BACKGROUND OF THE INVENTION
The present invention relates to various plasma processing apparatuses such as a plasma etching apparatus, an ashing apparatus, a film formation apparatus, and a sputtering apparatus and, more particularly, to a plasma processing apparatus excellent in terms of an improvement in uniformity of a plasma generated in the plasma processing apparatus, an increase in plasma generation efficiency, an increase in processing precision, a reduction in damage to a substrate, and the like.
Known plasma processing apparatuses are apparatuses for performing various processes such as ashing, etching, CVD processing, and sputtering in an apparatus of manufacturing a semiconductor integrated circuit. In these apparatuses, a high frequency (RF) induction plasma generation apparatus using a coiled antenna is known as an apparatus for generating a plasma. Further, a plasma processing apparatus is also known, which has a plasma generating electrode (e.g. a parallel plate electrode) installed in its plasma processing chamber.
An example of this RF induction plasma generation apparatus is disclosed in European Pat. Appln. KOKAI No. 379828. The RF induction plasma generation apparatus disclosed in European Pat. Appln. KOKAI No. 379828 has a wall opposing a wafer susceptor consisting of an insulator such as silica glass, and a coiled antenna fixed on the outer surface of the insulator wall. A processing gas is ionized by an RF electromagnetic field formed by flowing an RF current through this antenna, thereby generating a plasma.
An antenna division type RF induction plasma generation apparatus is also disclosed in European Pat. Appln. KOKAI No. 379828. In this antenna division type RF induction plasma generation apparatus, the antenna is constituted by two set of coiled antennas in order to precisely control, over a wide range, a generation region where a plasma is generated. An RF power is applied to each antenna.
This RF induction plasma generation apparatus is used as an apparatus for a charge elimination process of eliminating the charge of a jack, a cleaning process of cleaning the wall of a chamber, an etching process, and the like.
In addition, a parallel plate plasma processing system is known as an example of the plasma processing apparatus having a plasma generating electrode installed in the plasma processing chamber. In this parallel plate plasma processing system, two plate electrodes are opposed in the plasma processing or reaction chamber. One of the plate electrodes has a heater or a cooling line contained therein, and is disposed to mount thereon a to-be-processed object. An RF power is applied between the opposed two plate electrodes, thereby generating plasma of a reactive gas therebetween, which is to be used to, for example, etch the to-be-processed object.
The plasma processing apparatus of the antenna division RF induction type has a technical problem that the plasma is difficult to uniformly generate, and another technical problem that hunting occurs between the divided antennas. In addition, the etching selectivity and the etching shape must be controlled.
The plasma processing apparatus of the parallel plate electrode structure also has technical problems such as the difficulty of plasma's uniform generation, the occurrence of hunting between the electrodes, etc. Moreover, also in this case, the etching selectivity and the etching shape must be controlled.
BRIEF SUMMARY OF THE INVENTION
It is an object of the present invention to solve or reduce the above problems of the conventional plasma processing apparatus of the parallel plate electrode structure.
It is another object of the present invention to improve the uniformity of a plasma to be generated.
It is still another object of the present invention to prevent the occurrence of hunting between a plurality of electrodes.
It is still another object of the present invention to increase the plasma generation efficiency.
It is still another object of the present invention to enable the control of the etching selectivity and the control of the etching shape when plasma etching is performed by the plasma processing apparatus.
It is still another object of the present invention to control the plasma generation region so as to clean an arbitrary region and shorten the cleaning time, when the chamber of the plasma processing apparatus is cleaned with plasma.
According to a first aspect of the invention, there is provided a plasma processing apparatus comprising:
a plasma processing chamber;
a plasma generating electrode located in the plasma processing chamber;
a phase detecting circuit for detecting a phase of a high frequency power to be supplied to the plasma generating electrode;
a plasma generation high frequency power supply unit for supplying a plasma generating high frequency power to the plasma generating electrode, the plasma generation high frequency power supply unit having a phase controller for controlling the phase of the high frequency power supplied to the plasma generating electrode;
a lower electrode located in the processing chamber for mounting thereon a to-be-processed object; and
a bias high frequency power supply unit for supplying a biasing high frequency power to the lower electrode, the bias high frequency power supply unit having a phase controller for controlling a phase of the biasing high frequency power so as to delay the phase of the biasing high frequency power with respect to the phase of the high frequency power supplied to the plasma generating electrode.
Preferably, in the plasma processing apparatus, the phase controller in the plasma generation high frequency power supply unit controls the plasma generating high frequency power to be supplied to the plasma generating electrode so as to make a phase of the plasma generating high frequency power identical to a phase of the biasing high frequency power.
More preferably, in the plasma processing apparatus, the plasma generation high frequency power supply unit forms a high frequency power of a continuous wave as the plasma generating high frequency power to be supplied to the plasma generating electrode.
Also preferably, in the plasma processing apparatus, the plasma generation high frequency power supply unit forms a high frequency power of a continuous wave as the plasma generating high frequency power to be supplied to the plasma generating electrode, and the bias high frequency power supply unit forms a high frequency power pulse train as the biasing high frequency power to be supplied to the lower electrode, the phase controller controlling a phase of the high frequency power pulse train to be supplied to the lower electrode.
Yet preferably, the plasma processing apparatus further comprises a controller for controlling an ON/OFF duty ratio of the biasing high frequency power pulse train.
Yet further preferably, in the plasma processing apparatus, the plasma generating high frequency power unit forms a high frequency power pulse train as the plasma generating high frequency power to be supplied to the plasma generating electrode, and the phase controller controls a phase of the high frequency power pulse train to be supplied to the plasma generating electrode.
Preferably, in the plasma processing apparatus, the phase controller of the bias high frequency power supply unit controls the biasing high frequency power pulse train such that the biasing high frequency power pulse train has a predetermined delay with respect to the plasma generating high frequency power pulse train.
It is preferable that in the plasma processing apparatus, the bias high frequency power supply unit reduces a power value of the biasing high frequency power pulse train during an after glow period of pulse plasma.
It is also preferable that in the plasma processing apparatus, the bias high frequency power supply unit forms a biasing high frequency power pulse train which has a pulse width wider than a pulse width of the plasma generating high frequency power pulse train, and has a decreased power value during an after glow period of pul
Mills Gregory
Oblon & Spivak, McClelland, Maier & Neustadt P.C.
Powell Alva C
Tokyo Electron Limited
LandOfFree
Plasma processing apparatus does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Plasma processing apparatus, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Plasma processing apparatus will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2490882