Laser cutting with electron removal
A laser cutting process for ensuring a plasma plume or cloud that forms during a substrate cutting process does not lead to undesired re-deposition of material onto the substrate. At least one electrode is biased to draw the electrons of the plasma plume or cloud towards the electrode and away from the substrate. A vacuum port and/or a blower may be strategically located to ensure gas flow away from the substrate and hence, directing of the electrons away from the substrate. In so doing, material re-deposition is less likely to occur.
1 . A method, comprising:
disposing a substrate in a processing chamber on a surface of a substrate support, wherein the chamber includes a laser source inside the chamber;
laser cutting the substrate; and
directing electrons emitted during the laser cutting to a first electrode disposed in the processing chamber, wherein the directing comprises applying a bias to the first electrode and maintaining a second electrode at ground, wherein the second electrode is opposite to the first electrode, wherein the first electrode is powered and the second electrode is grounded, wherein the second electrode is coupled to ground, and wherein at least one electron density sensor is coupled to the first electrode.
2 . The method of claim 1 , further comprising evacuating the processing chamber.
3 . The method of claim 2 , wherein applying the bias creates an electric field direction, wherein evacuating the processing chamber creates a vacuum direction, and wherein the electric field direction and the vacuum direction are parallel.
4 . The method of claim 1 , further comprising directing gas from the second electrode to the first electrode during the laser cutting.
5 . The method of claim 4 , wherein applying the bias creates an electric field direction, wherein directing gas from the second electrode to the first electrode creates a gas flow direction, and wherein the electric field direction and the gas flow direction are parallel.
6 . The method of claim 1 , wherein directing the electrons results in an uneven plasma plume, wherein a greater percentage of the plasma plume is disposed adjacent the first electrode as compared to the second electrode.
7 . The method of claim 1 , wherein the directing comprises directing electrons in a direction perpendicular to the surface.
8 . The method of claim 1 , further comprising turning on a blower to push gas through the chamber.
9 . The method of claim 1 , wherein the surfaces of the first electrode and the second electrode that face the substrate are parallel to one another.
10 . The method of claim 9 , wherein the surfaces are perpendicular to a surface of the substrate.
11 . The method of claim 9 , wherein the surfaces are at an angle of 45 degrees relative to a surface of the substrate.
12 . The method of claim 9 , wherein the surfaces are at an angle of 0 degrees relative to a surface of the substrate.
13 . The method of claim 1 , wherein the chamber has a vacuum port aligned with the first electrode such that the vacuum is drawn towards the first electrode.
14 . The method of claim 1 , wherein the chamber has a blower disposed at a location aligned with the second electrode such that gas is directed towards the first electrode.
15 . The method of claim 1 , wherein a center of the first electrode is linearly aligned with at least a portion of the second electrode and the substrate.
16 . The method of claim 1 , wherein a surface of the first electrode that is facing the substrate is disposed at an angle of between 0 degrees and 90 degrees relative to the surface of the substrate support.
17 . The method of claim 16 , wherein at least a portion of the second electrode is disposed below the substrate support.
18 . The method of claim 1 , wherein the chamber comprises at least one vacuum port that is disposed at an angle relative to the surface, wherein the angle is between 0 degrees and 90 degrees.
19 . The method of claim 1 , further comprising at least one blower linearly aligned with the second electrode, wherein the at least one blower is disposed at an angle relative to the surface to cause electrons to be directed towards the first electrode.
20 . The method of claim 1 , wherein the bias applied is from a DC power source.