Apparatus for Plasma Processing
Apparatus and method for plasma-based processing well suited for deposition, etching, or treatment of semiconductor, conductor or insulating films. Plasma generating units include one or more elongated electrodes on the processing side of a substrate and a neutral electrode proximate the opposite side of the substrate. Gases may be injected proximate a powered electrode which break down electrically and produce activated species that flow toward the substrate area. This gas then flows into an extended process region between powered electrodes and substrate, providing controlled and continuous reactivity with the substrate at high rates with efficient utilization of reactant feedstock. Gases are exhausted via passages between powered electrodes or electrode and divider.
1 . An apparatus for plasma processing of a substrate comprising:
a processing chamber;
a support for positioning the substrate in the processing chamber for processing;
a first electrode in the processing chamber, the first electrode having a front surface facing the substrate and at least a first side surface, wherein a first gap is formed between the front surface of the first electrode and the substrate and a second gap is formed between the first side surface of the electrode and at least one other surface in the processing chamber;
a gas supply system and a gas exhaust system configured to induce a flow of gas through the first gap and the second gap; and
a power supply system configured to provide alternating current (AC) power to the first electrode such that a plasma is sustained in the first gap and the second gap;
wherein the first electrode has a length and a width, wherein the length of the first electrode is at least four times the width of the first electrode; and
wherein the first electrode is positioned such that the first gap and the second gap are each less than the width of the first electrode.
2 . The apparatus of claim 1 wherein the other surface is a side surface of a second electrode.
3 . The apparatus of claim 1 wherein the minimum distance from the first electrode to the substrate is less than about 15 mm.
4 . The apparatus of claim 1 wherein the minimum distance from the first electrode to the other surface is less than about 15 mm.
5 . The apparatus of claim 1 wherein the first side surface of the first electrode is substantially perpendicular to the front surface of the first electrode and wherein the first side surface of the first electrode is substantially parallel to the other surface in the processing chamber.
6 . The apparatus of claim 1 , wherein the gas supply system and the gas exhaust system are configured to induce a gas flow between the first electrode and the substrate and to exhaust gas away from the substrate along the side of the first electrode.
7 . The apparatus of claim 1 , wherein the gas supply system is configured to supply gas along the side of the first electrode, which flows toward the substrate and then between the first electrode and the substrate.
8 . The apparatus of claim 7 , wherein the gas exhaust system is configured to exhaust gas away from the substrate along a second side of the first electrode.
9 . The apparatus of claim 1 , wherein the gas supply system is configured to supply gas through the front surface of the first electrode and the gas exhaust system is configured to exhaust gas away from the substrate along the side of the first electrode.
10 . The apparatus of claim 9 , wherein the gas exhaust system is also configured to exhaust gas away from the substrate along a second side of the first electrode.
11 . The apparatus of claim 10 , wherein the first side surface and the second side surface of the first electrode are substantially perpendicular to the front surface of the first electrode.
12 . The apparatus of claim 1 , wherein the gas supply system includes a first gas inlet for injecting gas proximate the first side of the first electrode and at least a second gas inlet for injecting gas through the front surface of the first electrode.
13 . The apparatus of claim 1 , further comprising a gas supply system and a vacuum pump configured to maintain a gas pressure in the range of between about 400 Pascals and 10,000 Pascals during processing of the substrate.
14 . The apparatus of claim 1 , wherein the power supply is configured to provide power to the first electrode at a frequency in the range of between about 1 MHz and 82 MHz.
15 . The apparatus of claim 1 further comprising a dielectric liner proximate at least a front surface of the first electrode.
16 . The apparatus of claim 15 wherein the dielectric liner has substantially constant gap to the front surface of the electrode and substantially constant thickness over most of the area of the front surface of the electrode.
17 . An apparatus for plasma processing of a substrate comprising:
a processing chamber;
a support for positioning the substrate in the processing chamber for processing;
a plurality of electrodes in the processing chamber, each electrode having a front surface facing the substrate and at least a first side surface, wherein a first gap is formed between the front surface of the respective first electrode and the substrate;
a gas supply system and a gas exhaust system configured to induce a flow of gas through the first gap between each respective electrode and the substrate and along the first side surface of each electrode; and
a power supply system configured to provide alternating current (AC) power to each electrode such that a plasma is sustained in the first gap between each respective electrode and the substrate;
wherein each electrode has a length and a width, wherein the length of each respective electrode is at least four times the width of the respective electrode;
wherein each electrode is positioned such that the first gap between each respective electrode and the substrate is less than the width of the respective electrode; and
wherein each respective electrode is spaced from an adjacent electrode by a distance that is less than the width of the respective electrode.
18 . The apparatus of claim 17 wherein the plurality of electrodes includes at least three electrodes.
19 . The apparatus of claim 17 wherein the distance between each respective electrode and the adjacent electrode is less than about 15 mm.
20 . The apparatus of claim 17 , further comprising a grounded element between at least one of the electrodes and an adjacent electrode.
21 . The apparatus of claim 17 , further comprising a dielectric element between at least one of the electrodes and an adjacent electrode.
22 . The apparatus of claim 17 wherein the minimum distance from each electrode to the substrate is less than about 20 mm.
23 . The apparatus of claim 17 , wherein the gas supply system and the gas exhaust system are configured to induce a gas flow between each respective electrode and an adjacent electrode.
24 . The apparatus of claim 17 , wherein the gas supply system and the gas exhaust system are configured to supply gas along one of the sides of each respective electrode and exhaust gas along an other side of the respective electrode.
25 . The apparatus of claim 17 , further comprising a gas supply system and a vacuum pump configured to maintain a gas pressure in the range of between about 400 Pascals and 10,000 Pascals during processing of the substrate.
26 . The apparatus of claim 17 , wherein the support forms a plurality of gas inlets proximate the substrate and a plurality of exhaust outlets proximate the substrate, wherein each of the respective gas inlets in the support has a dimension across the respective gas inlet that is less than about 1 mm and wherein each of the respective gas outlets in the support has a dimension across the respective gas outlet that is less than about 1 mm.