Substrate breakage detection in a thermal processing system
Apparatus, systems, and processes for substrate breakage detection in a thermal processing system are provided. In one example implementation, a process can include: accessing data indicative of a plurality of temperature measurements for a substrate, the plurality of measurements obtained during a cool down period of a thermal process; estimating one or more metrics associated with a cooling model based at least in part on the data indicative of the plurality of temperature measurements; and determining a breakage detection signal based at least in part on the one or more metrics associated with the cooling model. The breakage detection signal is indicative of whether the substrate has broken during thermal processing.
1. A process for breakage detection in a thermal processing system, comprising:
accessing data indicative of a plurality of temperature measurements for a substrate, the plurality of measurements obtained during a cool down period for the substrate during a thermal process;
estimating one or more metrics associated with a cooling model based at least in part on the data indicative of the plurality of temperature measurements; and
determining a breakage detection signal based at least in part on the one or more metrics associated with the cooling model, the breakage detection signal indicative of whether the substrate has broken during thermal processing.
2. The process of claim 1 , wherein when the breakage detection signal is indicative of a non-broken substrate, the process includes processing a next substrate in the thermal processing system.
3. The process of claim 1 , wherein when the breakage detection signal is indicative of a broken substrate, the process includes performing a corrective action prior to processing a next substrate in the thermal processing system.
4. The process of claim 3 , wherein the corrective action comprises:
moving a next substrate for thermal processing back to a cassette;
opening a door of the thermal processing chamber; and
removing one or more pieces of the broken substrate from the processing chamber.
5. The process of claim 1 , wherein the plurality of temperature measurements comprise one or more temperature measurements associated with a top surface of the substrate and one or more temperature measurements associated with a bottom surface of the substrate.
6. The process of claim 1 , wherein the one or more metrics comprise a cooling model parameter.
7. The process of claim 1 , wherein the one or more metrics comprise a model fitting error.
8. The process of claim 1 , wherein the cooling model is based at least in part on Newton's law of cooling.
9. The process of claim 8 , wherein the one or more metrics comprise a cooling model parameter comprises an exponential cooling constant in Newton's law of cooling.
10. The process of claim 7 , wherein the model fitting error comprises a root mean square error.
11. The process of claim 1 , wherein determining a breakage detection signal based at least in part on the one or more metrics associated with the cooling model comprises:
comparing the one or more metrics to a predetermined range of metrics;
determining the breakage detection signal based at least in part on whether the one or more metrics falls within the predetermined range of metrics.
12. The process of claim 11 , wherein the predetermined range of metrics comprises a range of metrics associated with a non-broken substrate.
13. The process of claim 11 , wherein the predetermined range of metrics comprises a range of metrics associated with a broken substrate.
14. The process of claim 11 , wherein determining a breakage detection signal based at least in part on the one or more metrics associated with the cooling model comprises:
dividing the data indicative of a plurality of temperature measurements into a plurality of sets, each set associated with a predetermined time interval;
determining one or more metrics associated with the cooling model for each set;
determining at least one value associated with the one or more metrics determined for each set;
comparing the value to a predetermined range of values;
determining the breakage detection signal based at least in part on whether the at least on value falls within the predetermined range of values.
15. The process of claim 14 , wherein the value is determined based at least in part on a mean or standard deviation of the one or more metrics determined for each set.