Processes for testing a region for an analyte and a process for forming an electronic device
View Patent ↗A workpiece, including a substrate and overlying layer, can be exposed to a region, such as a process chamber, to test for the presence of an analyte. Detected fluorescence emission signals during TXRD due to the substrate are significantly reduced, allowing the analyte to be detected at lower concentrations. In one embodiment, the substrate can principally include silicon, and the layer can include an organic layer (e.g., resist, polyimide, etc.) The organic layer allows analytes with an atomic number as low as 11 to be detected. Also, the detection limits for nearly all analytes can be reduced because the detector is not receiving a disproportionately larger number of fluorescence emission from silicon. In additional, areal information regarding the analyte with respect to position over the substrate can be obtained. Detection levels as low as 1 E 9 atoms/cm 2 are possible.
1. A process for forming an electronic device comprising:
testing a processing chamber for an analyte by:
exposing a workpiece to the processing chamber, wherein the workpiece includes a first substrate and an organic layer overlying the first substrate, wherein the organic layer comprises a substantially different material compared to the first substrate; and
using XRF spectroscopy to analyze the workpiece for the analyte;
determining whether a concentration level of the analyte is no greater than a threshold value; and
processing a second substrate within the processing chamber when the concentration level of the analyte is no greater than a threshold value, wherein the second substrate:
is different from the first substrate; and
comprises an electronic device substrate that includes the electronic device that is at least partially fabricated after processing the second substrate within the processing chamber is completed.
2. The process of claim 1 , wherein the processing chamber is capable of being evacuated to a pressure less than approximately 1 Torr.
3. The process of claim 1 , wherein:
cleaning the processing chamber after determining whether a concentration level of the analyte is no greater than a threshold value and before processing a second substrate within the processing chamber;
testing the processing chamber another time for the analyte using another workpiece, wherein testing includes using the XRP spectroscopy and is performed after cleaning the processing chamber; and
determining whether a concentration level of the analyte for the other workpiece is no greater than the threshold value.
4. The process of claim 1 , wherein the organic layer comprises a resist material.
5. The process of claim 1 , further comprising:
removing the organic layer from the workpiece after testing the processing chamber;
forming a resist layer over the first substrate to form another workpiece, wherein forming the resist layer is performed after removing the organic layer;
testing the processing chamber another time for the analyte, wherein testing includes using the XRF spectroscopy; and
determining whether a concentration level of the analyte for the other workpiece is no greater than a threshold value.
6. The process of claim 1 , wherein the analyte includes an element with an atomic number of at least 11.
7. The process of claim 6 , wherein the analyte includes a element with an atomic number no greater than 18.
8. The process of claim 7 , wherein the electronic device comprises a metal-insulator-semiconductor field-effect-transistor.
9. The process of claim 8 , the organic layer has a thickness sufficient to substantially prevent excitation of the substrate during using the XRF spectroscopy.
10. The process of claim 8 , wherein the thickness of the organic layer is at least approximately 300 nm thick.