Magnetic field assisted deposition
Embodiments relate to applying a magnetic field across the paths of injected polar precursor molecules to cause spiral movement of the precursor molecules relative to the surface of a substrate. When the polar precursor molecules arrive at the surface of the substrate, the polar precursor molecules make lateral movements on the surface due to their inertia. Such lateral movements of the polar precursor molecules increase the chance that the molecules would find and settle at sites (e.g., nucleation sites, broken bonds and stepped surface locations) or react on the surface of the substrate. Due to the increased chance of absorption or reaction of the polar precursor molecules, the injection time or injection iterations may be reduced.
1. A method of depositing a layer of material on a substrate, comprising:
generating radicals as precursor molecules by applying voltage across electrodes in a reactor that is at least partially enclosed within a process chamber;
injecting the precursor molecules into a reactor chamber formed in the reactor;
injecting the precursor molecules towards substrate by a reactor;
applying a magnetic field by magnets placed within the process chamber and attached to the reactor, the magnet field traversing paths of the precursor molecules traveling within the reactor chamber to the substrate to cause spiral movements of the precursor molecules relative to a surface of the substrate;
exposing the surface of the substrate to the precursor molecules making the spiral movements to cause the surface of the substrate to absorb or react with the precursor molecules; and
causing the substrate to move in parallel to the surface of the substrate to expose different parts of the substrate to the precursor molecules.
2. The method of claim 1 , further comprising discharging excess precursor molecules remaining after exposing the surface of the substrate to the injected precursor molecules.
3. The method of claim 1 , wherein the magnetic field is generated by permanent magnets or electromagnets.
4. The method of claim 1 , further comprising performing atomic layer deposition (ALD) on the substrate by exposing the surface of the substrate to the precursor molecules.
5. The method of claim 4 , wherein the precursor molecules are ones selected from a group consisting of methylsilane, dimethylaluminumhydride (DMAH) and dimethylethylamine alane (DMEAA).
6. The method of claim 1 , further comprising passing precursor molecules remaining after exposure of the surface to the substrate through a constriction zone formed in the reactor, a first height of the reactor chamber larger than a second height of the constriction zone.
7. The method of claim 6 , further comprising discharging the remaining precursor molecules through an exhaust portion formed in the reactor.
8. The method of claim 1 , wherein two magnets of asymmetric configuration are placed at both sides of the reactor chamber to generate the magnetic field.