Real-time detection of particulate matter during deposition chamber manufacturing
Implementations disclosed describe a system that includes a deposition chamber, a light source to produce an incident beam of light, wherein the incident beam of light is to illuminate a region of the deposition chamber, and a camera to collect a scattered light originating from the illuminated region of the deposition chamber, wherein the scattered light is to be produced upon interaction of the first incident beam of light with particles inside the illuminated region of the deposition chamber. The described system may optionally have a processing device, coupled to the camera, to generate scattering data for a plurality of locations of the illuminated region, wherein the scattering data for each location comprises intensity of the scattered light originating from this location.
1 . A system comprising:
a process chamber;
an illumination system to produce a first incident beam of light, wherein the first incident beam of light illuminates a region of the process chamber; and
a light detector to:
generate light scattering data comprising an intensity map of scattered light for at least a portion of the illuminated region, the scattered light produced upon interaction of the first incident beam of light with particles in the illuminated region, wherein the intensity map comprises a background portion and a plurality of maxima; and
a processing device communicatively coupled to the light detector, the processing device to:
determine, using the background portion of the intensity map, a density of plasma-forming particles of a first size in the illuminated region; and
determine, using the plurality of maxima of the intensity map, a density of contaminant particles of a second size in the illuminated region.
2 . The system of claim 1 , wherein the illumination system is further to produce a second incident beam of light, wherein the second incident beam of light improves uniformity of illumination of at least a part of the illuminated region compared with uniformity of illumination of the part of the illuminated region by the first incident beam of light.
3 . The system of claim 2 , wherein the second incident beam of light enters the process chamber from a different direction compared with the first incident beam of light.
4 . The system of claim 2 , wherein the illumination system comprises:
a first light source to generate the first incident beam of light, and
a second light source to generate the second incident beam of light.
5 . The system of claim 4 , wherein at least one of the first light source or the second light source comprises a laser light source.
6 . The system of claim 2 , wherein the illumination system comprises a beam splitter to produce, using a common beam of light, the first incident beam of light and the second incident beam of light.
7 . The system of claim 1 , wherein the illumination system comprises a cylindrical lens that expands the first incident beam of light.
8 . The system of claim 1 , wherein the plasma-forming particles of the first size comprise atomic-size particles in the process chamber.
9 . The system of claim 8 , wherein the processing device is further to:
determine, using the density of the plasma-forming particles of the first size, a uniformity of the plasma in the process chamber.
10 . The system of claim 1 , wherein the light detector is to collect the scattered light from a plurality of depths within the illuminated region, wherein to collect the scattered light from the plurality of depths, the light detector is to:
change a focus to each depth of the plurality of depths, wherein to change the focus, the light detector is to change at least one of:
a focal distance of the light detector, or
a distance from a lens of the light detector to the illuminated region.
11 . A system comprising:
a process chamber;
one or more light sources to generate:
a first incident beam of light, wherein the first incident beam of light illuminates a region of the process chamber, and
a second incident beam of light, wherein the second incident beam of light improves uniformity of illumination of at least a part of the illuminated region of the process chamber compared with uniformity of illumination of the part of the illuminated region of the process chamber by the first incident beam of light, the first incident beam of light having intensity that decreases along a direction within the region of the process chamber and the second incident beam of light having intensity that increases along the direction within the region of the process chamber;
a light detector to:
collect light scattering data characterizing scattered light produced by one or more particles, individual particles being illuminated simultaneously by both the first incident beam of light and the second incident beam of light; and
a processing device communicatively coupled to the light detector, the processing device to:
determine, based on the light scattering data, a distribution of the one or more particles in the process chamber.
12 . A method comprising:
illuminating, using a first incident beam of light, a region of a process chamber;
obtaining scattering data comprising an intensity map of scattered light for at least a portion of the illuminated region, the scattered light produced upon interaction of the first incident beam of light with particles in the illuminated region, wherein the intensity map comprises a background portion and a plurality of maxima;
determining, using the background portion of the intensity map, a density of plasma-forming particles of a first size in the illuminated region; and
determining, using the plurality of maxima of the intensity map, a density of contaminant particles of a second size in the illuminated region.
13 . The method of claim 12 , further comprising:
illuminating the region of the process chamber using a second incident beam of light, wherein the second incident beam of light improves uniformity of illumination of at least a part of the illuminated region compared with uniformity of illumination of the part of the illuminated region by the first incident beam of light.
14 . The method of claim 13 , wherein the second incident beam of light enters the process chamber from a different direction compared with the first incident beam of light.
15 . The method of claim 13 , wherein the first incident beam of light is generated using a first light source, and the second incident beam of light is generated using a second light source.
16 . The method of claim 13 , wherein the first incident beam of light and the second incident beam of light are generated, using a beam splitter, from a common beam of light.
17 . The method of claim 12 , wherein the first incident beam of light is expanded using a cylindrical lens.
18 . The method of claim 12 , wherein the plasma-forming particles of the first size comprise atomic-size particles in the process chamber.
19 . The method of claim 18 , further comprising:
determining, using the density of the plasma-forming particles of the first size, a uniformity of the plasma in the process chamber.
20 . The method of claim 12 , wherein obtaining the scattering data comprises:
changing a focus of a light detector to each depth of a plurality of depths of the illuminated region, wherein changing the focus of the light detector comprises changing at least one of:
a focal distance of the light detector, or
a distance from a lens of the light detector to the illuminated region.