METAL CHLORIDE GAS GENERATION METHOD AND APPARATUS
A metal chloride gas generation method includes generating a plasma of a chlorine-containing source gas, and reacting chlorine ions or radicals from the plasma with a solid target metal source to generate the metal chloride gas.
1 . A metal chloride gas generation method, comprising:
generating a plasma of a chlorine-containing source gas; and
reacting chlorine ions or radicals from the plasma with a solid target metal source to generate the metal chloride gas.
2 . The method of claim 1 , wherein the chlorine-containing source gas comprises a mixture of chlorine gas and an inert gas.
3 . The method of claim 2 , wherein the inert gas comprises argon or nitrogen.
4 . The method of claim 2 , wherein:
the solid target metal source comprises an aluminum, tantalum, titanium, copper or vanadium solid target metal source; and
the metal chloride gas comprises AlCl 3 , TaCl 5 , TiCl 4 , CuCl 2 or VCl 4 .
5 . The method of claim 4 , wherein:
the solid target metal source comprises the aluminum solid target metal source; and
the metal chloride gas comprises the AlCl 3 .
6 . The method of claim 5 , further comprising forming an aluminum oxide layer on a substrate by atomic layer deposition by alternately providing the AlCl 3 gas and an oxidizer gas into a vacuum enclosure of an atomic layer deposition tool in which the substrate is located.
7 . The method of claim 1 , further comprising:
providing the metal chloride gas to a buffer tank;
storing the metal chloride gas in the buffer tank; and
providing the metal chloride gas from the buffer tank to a process unit to etch a material located on a substrate in the process unit or to deposit a material layer on a substrate located in the process unit.
8 . The method of claim 7 , wherein the process unit comprises an atomic layer deposition tool, and the metal chloride gas and an oxidizer gas are alternately provided into a vacuum enclosure of the atomic layer deposition tool to deposit the material layer comprising a metal oxide on the substrate by atomic layer deposition.
9 . The method of claim 7 , further comprising providing an inert carrier gas to the buffer tank separately from the metal chloride gas, wherein the metal chloride gas provided from the buffer tank to the process unit is mixed with the inert carrier gas.
10 . The method of claim 2 , wherein the solid target metal source comprises a sputtering target.
11 . The method of claim 10 , wherein:
the sputtering target comprises an electrode of a direct current power supply used to generate the plasma;
the plasma comprises ions or radicals of the chlorine gas and ions of the inert gas;
the ions of the inert gas sputter metal atoms from the sputtering target; and
the sputtered metal atoms react with the ions or radicals of the chlorine gas to form the metal chloride gas.
12 . The method of claim 10 , wherein the sputtering target comprises a planar sputtering target and the plasma is generated over a planar surface of the planar sputtering target.
13 . The method of claim 10 , wherein the sputtering target comprises a hollow cylindrical sputtering target comprising a cylindrical cavity therein, and the plasma is generated inside the cylindrical cavity.
14 . The method of claim 2 , wherein:
the plasma of the chlorine-containing source gas is generated in an alternating current powered plasma chamber;
the solid target metal source is located downstream from the plasma chamber;
the plasma comprises ions or radicals of the chlorine gas which are provided downstream from the plasma chamber to a surface of the solid target metal source to form metal chloride molecules; and
the metal chloride molecules are sublimated to form the metal chloride gas.
15 . The method of claim 14 , wherein the plasma chamber comprises an anode electrode, a cathode electrode, and at least one insulating spacer between the cathode electrode and the plasma.
16 . The method of claim 15 , wherein the anode electrode and the cathode electrode comprise parallel plate electrodes connected to a direct current power source.
17 . The method of claim 15 , wherein the cathode electrode comprises a hollow cylindrical electrode comprising a cylindrical cavity therein and connected to an alternating current power source, the at least one insulating spacer is located in the cylindrical cavity, and the plasma is generated inside the cylindrical cavity.
18 . The method of claim 2 , wherein the plasma is generated in a plasma chamber, and the chlorine gas and the inert gas are provided to the plasma chamber through separate mass flow controllers to control a ratio of the chlorine gas to the inert gas.
19 . A method, comprising:
generating a metal chloride gas in a metal chloride gas generator;
providing the metal chloride gas from the metal chloride gas generator to a buffer tank through a first gas flow conduit;
storing the metal chloride gas in the buffer tank; and
providing the metal chloride gas from the buffer tank to a process unit through a second gas flow conduit to etch a material located on a substrate in the process unit or to deposit a material layer on a substrate located in the process unit.
20 . An apparatus, comprising:
a metal chloride gas generator configured to generate a process source gas comprising a metal chloride gas, wherein the metal chloride gas generator comprises a plasma generator configured to generate a plasma of a chlorine-containing source gas, and a solid target metal source that is exposed to or is located downstream of the plasma generator;
a process unit comprising a vacuum enclosure configured to hold a substrate therein and to receive the process source gas; and
a buffer tank located between the metal chloride gas generator and the process unit, and configured to receive the process gas from the metal chloride gas generator and to provide the process source gas to the process unit.