摘要:
Methods and systems for calibrating a temperature control system in a vapor deposition chamber. A temperature sensor senses temperature within a semiconductor processing chamber and generates an output signal. A temperature control system controls a chamber temperature by controlling a heating apparatus based on the output signal. A method includes instructing the control system to target a setpoint temperature, and depositing a layer of material onto a surface in the chamber by a vapor deposition process. A variation of a property of the layer is measured while depositing the layer, the property known to vary cyclically as a thickness of the layer increases. The measured property is allowed to vary cyclically for one or more cycles. If there is a difference between a time period of one or more of the cycles and an expected time period associated with the setpoint temperature, the temperature control system is adjusted based on the difference.
摘要:
A substrate support system comprises a relatively thin circular substrate holder having a plurality of passages extending between top and bottom surfaces thereof. The substrate holder includes a single substrate support ledge or a plurality of substrate support spacer vanes configured to support a peripheral portion of the substrate backside so that a thin gap is formed between the substrate and the substrate holder. The vanes can be angled to resist backside deposition of reactant gases as the substrate holder is rotated. A hollow support member provides support to an underside of the substrate holder. The hollow support member is configured to convey gas (e.g., inert gas or cleaning gas) upward into one or more of the passages of the substrate holder. The upwardly conveyed gas flows into the gap between the substrate and the substrate holder. Depending upon the embodiment of the invention, the gas in the gap can then flow either (1) outward and upward around the substrate edge or (2) downward through passages of the substrate holder, if any, that do not lead back into the hollow support member. The gas that flows outward and upward around the substrate edge inhibits backside deposition of reactant gases above the substrate. The gas that flows downward through the passages that do not lead back to the support member advantageously inhibits autodoping by sweeping out-diffused dopant atoms away from the substrate front side. In one embodiment, the support member comprises a hollow multi-armed support spider that conveys gas into selected ones of the passages. In another embodiment, the support member comprises a bowl- or cup-shaped structure that conveys gas upward into all of the passages. In yet another embodiment, the support member comprises a bowl- or cup-shaped structure that conveys gas upward into all but one or more of the passages.
摘要:
A method and system are disclosed for verifying the flow rate of gas through a mass flow controller, such as a mass flow controller used with a tool for semiconductor or solar cell fabrication. To verify the mass flow rate measured by the mass flow controller, gas passing through the mass flow controller is also passed through a mass flow meter. The measured flow rate through the mass flow controller is compared to the measured flow rate through the mass flow meter and any difference between the two measured flow rates is determined. Depending upon the magnitude of any difference, the flow of gas to the mass flow controller may be altered.