Optimized saddle nozzle design for gas injection system

A system for depositing material over a sample in a localized region of the sample, the system comprising:

• a vacuum chamber;
• a sample support configured to hold a sample within the vacuum chamber during a sample evaluation process;
• a charged particle beam column configured to direct a charged particle beam into the vacuum chamber toward the sample such that the charged particle beam collides with the sample in a deposition region;
• a gas injection system configured to deliver a process gas to the deposition region of the sample, the gas injection system including an elongated gas conduit comprising:
• a first gas conduit segment configured to be coupled with a gas reservoir;
• a second gas conduit segment fluidly coupled to the first gas conduit segment and defining a downward curve of the elongated gas conduit;
• a third gas conduit segment defining an upward curve of the elongated gas conduit that extends to a sealed end and is disposed in a mirrored relationship with at least a portion of the second gas conduit;
• and
• a central gas conduit segment coupled between the second and third gas conduit segments, the central gas conduit segment having a first aperture formed in an upper surface of the central gas conduit and a second aperture, larger than the first aperture, formed in a lower surface of the central gas conduit directly across from the first aperture, wherein the elongated gas conduit has an inner diameter along a portion of its length that includes at least the second, third and central gas conduit segments and wherein the central gas conduit segment includes a substantially horizontal portion that extends on each side of the first and second apertures for a distance that is at least twice the inner diameter of the gas conduit.

A method of depositing material over a sample in a deposition region of the sample with a charged particle beam column, the method comprising:

• positioning a sample within a vacuum chamber such that the deposition region is under a field of view of the charged particle beam column;
• injecting a deposition precursor gas, with a gas injection system including an elongated gas conduit, into the vacuum chamber at a location adjacent to the deposition region;
• generating a charged particle beam with the charged particle beam column and focusing the particle beam within the deposition region of the sample;
• and
• scanning the focused particle beam across the deposition region of the sample to activate molecules of the deposition gas that have adhered to the sample surface in the deposition region and deposit material on the sample within the deposition region,
• wherein, the elongated gas conduit comprises:
• a first gas conduit segment configured to be coupled with a gas reservoir;
• a second gas conduit segment fluidly coupled to the first gas conduit segment and defining a downward curve of the elongated gas conduit;
• a third gas conduit segment defining an upward curve of the elongated gas conduit that extends to a sealed end and is disposed in a mirrored relationship with at least a portion of the second gas conduit;
• and
• a central gas conduit segment coupled between the second and third gas conduit segments, the central gas conduit segment having a first aperture formed in an upper surface of the central gas conduit and a second aperture, larger than the first aperture, formed in a lower surface of the central gas conduit directly across from the first aperture, wherein the elongated gas conduit has an inner diameter along a portion of its length that includes at least the second, third and central gas conduit segments and wherein the central gas conduit segment includes a substantially horizontal portion that extends on each side of the first and second apertures for a distance that is at least twice the inner diameter of the gas conduit.