Systems and methods for analyzing defects in CVD films
Embodiments of the present technology may include semiconductor processing methods that include depositing a film of semiconductor material on a substrate in a substrate processing chamber. The deposited film may be sampled for defects at greater than or about two non-contiguous regions of the substrate with scanning electron microscopy. The defects that are detected and characterized may include those of a size less than or about 10 nm. The methods may further include calculating a total number of defects in the deposited film based on the sampling for defects in the greater than or about two non-contiguous regions of the substrate. At least one deposition parameter may be adjusted as a result of the calculation. The adjustment to the at least one deposition parameter may reduce the total number of defects in a deposition of the film of semiconductor material.
1. A semiconductor processing method comprising:
depositing a film of semiconductor material on a substrate in a substrate processing chamber;
sampling for defects in the deposited film at greater than or about two non-contiguous regions of the substrate with scanning electron microscopy, wherein the defects are characterized by a size less than or about 10 nm;
calculating a total number of defects in the deposited film based on the sampling for defects in the greater than or about two non-contiguous regions of the substrate; and
adjusting at least one deposition parameter chosen from deposition temperature, deposition pressure, an amount of spacing between the substrate and a showerhead in the substrate processing chamber, and a flow rate ratio of two or more deposition precursors, wherein the adjustment to the at least one deposition parameter reduces the total number of defects in a deposition of the film of semiconductor material.
2. The semiconductor processing method of claim 1 , wherein the adjusting of the at least one deposition parameter reduces the total number of defects in a subsequently-deposited film of the semiconductor material by greater than or about 80%.
3. The semiconductor processing method of claim 1 , wherein the sampled film of semiconductor material is characterized by a calculated total number of defects greater than or about 10,000, and the adjustment to the at least one deposition parameter reduces the calculated total number of defects in a subsequently-deposited film of the semiconductor material to less than or about 2000.
4. The semiconductor processing method of claim 1 , wherein the adjusting of the at least one deposition parameter reduces an average surface roughness in a subsequently-deposited film of the semiconductor material by greater than or about 50%.
5. The semiconductor processing method of claim 1 , wherein the non-contiguous regions that are sampled for defects in the deposition film are characterized by a field of view of about 5 μm.
6. The semiconductor processing method of claim 1 , wherein the substrate upon which the film of semiconductor material is deposited is a planar substrate.
7. The semiconductor processing method of claim 1 , wherein the deposited film of semiconductor material comprises a silicon-containing dielectric material.
8. The semiconductor processing method of claim 1 , wherein the deposited film of semiconductor material is characterized by a thickness of less than or about 50 Å.
9. A semiconductor processing method comprising:
depositing a film of silicon oxide on a substrate in a substrate processing chamber, wherein the silicon oxide film is characterized by a thickness of less than or about 50 Å;
sampling for defects in the deposited silicon oxide film at greater than or about two non-contiguous regions of the substrate with scanning electron microscopy, wherein the defects are characterized by a size less than or about 10 nm; and
adjusting at least one deposition parameter chosen from deposition temperature, deposition pressure, an amount of spacing between the substrate and a showerhead in the substrate processing chamber, and a flow rate ratio of two or more deposition precursors, wherein the adjustment to the at least one deposition parameter reduces the number of defects sampled in a subsequent deposition of the silicon oxide film.
10. The semiconductor processing method of claim 9 , wherein the deposited silicon oxide layer is sampled for defects in the absence of an over layer that increases the size of the defects.
11. The semiconductor processing method of claim 9 , wherein the deposited silicon oxide layer is sampled for defects before a post-deposition anneal of the silicon oxide layer.
12. The semiconductor processing method of claim 9 , wherein the greater than or about two non-contiguous regions of the substrate are planar regions of the substrate.
13. The semiconductor processing method of claim 9 , wherein the sampled silicon oxide film is characterized by a total number of defects greater than or about 20,000, and the adjustment to the at least one deposition parameter reduces the total number of defects in a subsequently-deposited silicon oxide film to less than or about 1000.
14. The semiconductor processing method of claim 9 , wherein the adjustment to the at least one deposition parameter comprises reducing deposition pressure and increasing a flow rate ratio of a silicon-containing precursor to a non-silicon-containing precursor.
15. A semiconductor processing system comprising:
a deposition chamber to deposit a film of semiconductor material on a substrate in the deposition chamber;
a defect sampling unit comprising a scanning electron microscope, wherein the defect sampling unit is operable to receive the substrate with the deposited film of semiconductor material and sample the substrate for defects in the deposited film at greater than or about two non-contiguous regions of the substrate; and
a control unit in electronic communication with the deposition chamber to control one or more deposition parameters chosen from deposition temperature, deposition pressure, an amount of spacing between the substrate and a showerhead in the substrate processing chamber, and a flow rate ratio of two or more deposition precursors, wherein the control unit adjusts at least one of the deposition parameters in response to a number of defects in the deposited film of semiconductor material detected by the defect sampling unit so that a subsequent deposition of the film of semiconductor material has a reduced number of defects.
16. The semiconductor processing system of claim 15 , wherein the defects in the film of semiconductor material that are sampled by the defect sampling unit are characterized by a size less than or about 10 nm.
17. The semiconductor processing system of claim 15 , wherein the non-contiguous regions that are sampled for defects by the defect sampling unit are characterized by a field of view greater than or about 5 μm.
18. The semiconductor processing system of claim 15 , wherein the defect sampling unit samples the substrate at greater than or about ten non-contiguous regions that are equally spaced from each other around the substrate.
19. The semiconductor processing system of claim 15 , wherein the greater than or about two non-contiguous regions of the substrate are planar regions of the substrate.
20. The semiconductor processing system of claim 15 , wherein the defect sampling unit further comprises programmable logic that calculates a total number of defects in the deposited film on the substrate based on a number of sampled defects detected by the defect sampling unit, and wherein the control unit adjusts the at least one of the deposition parameters in response to the total number of defects calculated by the programmable logic of the defect sampling unit.