Low vapor pressure chemical delivery

1. An apparatus for delivery of a gas to a semiconductor processing system, comprising:

a gas inlet line having an inlet valve coupled to a chemical ampoule inlet of a chemical ampoule;

a gas outlet line having an outlet valve disposed downstream of a chemical ampoule outlet valve, and an outlet isolation valve disposed downstream of the outlet valve;

a gas flow controller arranged to control flow through the inlet valve;

an orifice sized to fit and be contained within the gas outlet line downstream of the outlet isolation valve, wherein the area of the orifice is sized to provide a choked flow through the gas outlet line; and

an orifice calibration circuit coupled to the gas outlet line downstream of a sensor, wherein the sensor is disposed downstream of the orifice.

2. The apparatus of claim 1 further comprising a check valve within the gas inlet line.

3. The apparatus of claim 1 wherein the sensor is arranged to provide a metric of at least one of flow, pressure, or chemistry from gas exiting the outlet valve.

4. The apparatus of claim 3 further comprising a controller configured to adjust a characteristic of a gas flowing within the gas inlet line in response to the metric provided to the controller by the sensor.

5. The apparatus of claim 3 further comprising a third outlet valve coupled to the gas outlet line and a heated divert line by-passing the chemical ampoule, wherein a processing chamber is coupled to the gas outlet line.

6. The apparatus of claim 5 further comprising a fourth outlet valve in fluid communication with the gas outlet line, allowing the flow of a chemical precursor and/or a carrier gas from the chemical ampoule to a processing chamber.

7. The apparatus of claim 1 , wherein the chemical ampoule is a sublimation ampoule, an evaporation ampoule, or a combination thereof.

8. The apparatus of claim 1 further comprising a purge line comprising a purge outlet valve in fluid communication with the purge line to flow a purge gas to a processing chamber.

9. The apparatus of claim 8 further comprising a calibration circuit configured for calibrating an effective open area of a valve by measuring a flow through the inlet valve and outlet valve while the flow is maintained through the inlet valve and outlet valve.

10. The apparatus of claim 1 , wherein the orifice calibration circuit is configured to calibrate an area of the orifice by measuring a flow through the orifice while the flow is maintained through the inlet valve and the outlet valve.

11. The apparatus of claim 1 , further comprising a check valve fluidly connected to the gas inlet line upstream of the chemical ampoule inlet.

12. An apparatus for delivery of a gas to a semiconductor processing system, comprising:

a gas inlet line having an inlet valve coupled to a chemical ampoule;

a gas outlet line having one or more of an outlet valve, a chemical ampoule outlet valve, or an outlet isolation valve for coupling the chemical ampoule to a processing chamber;

a gas flow controller arranged to control flow through the inlet valve;

an orifice fluidly coupled to the outlet valve, the gas outlet line, or a combination thereof;

a hot can in fluid communication with the chemical ampoule;

a check valve fluidly connected to the gas inlet line upstream of the chemical ampoule;

a third outlet valve coupled to the gas outlet line and a heated divert line by-passing the chemical ampoule, wherein the processing chamber is coupled to the gas outlet line; and

a fourth outlet valve in fluid communication with the gas outlet line, allowing a flow of chemical precursor and/or carrier gas from the chemical ampoule to the processing chamber.

13. The apparatus of claim 12 further comprising a sensor arranged to provide a metric of at least one of flow, pressure, or chemistry from gas exiting the outlet valve.

14. The apparatus of claim 13 further comprising a controller configured to adjust a characteristic of a gas flowing within the gas inlet line in response to the metric provided to the controller by the sensor.

15. The apparatus of claim 12 , wherein the chemical ampoule is a sublimation ampoule, an evaporation ampoule, or a combination thereof.

16. The apparatus of claim 12 further comprising a calibration circuit coupled to the gas outlet line.

17. The apparatus of claim 12 further comprising a purge line comprising a purge outlet valve in fluid communication with the purge line to flow a purge gas to the processing chamber.

18. An apparatus for delivery of a gas to a semiconductor processing system, comprising: a gas inlet line having an inlet valve coupled to a chemical ampoule; a gas outlet line having a first outlet valve coupled to the chemical ampoule and a process chamber; a gas flow controller arranged to control flow through the inlet valve; a hot can in fluid communication with the chemical ampoule; a check valve fluidly connected to the gas inlet line upstream of a heated divert line by-passing the chemical ampoule; an orifice fluidly coupled to the first outlet valve, gas outlet line, or a combination thereof; a second outlet valve coupled to the gas outlet line and the heated divert line; a third outlet valve in fluid communication with the gas outlet line, allowing a flow of chemical precursor and/or carrier gas from the chemical ampoule to the processing chamber; and a calibration circuit coupled to the first outlet valve.

19. The apparatus of claim 18 , further comprising a sensor arranged to provide a metric of at least one of flow, pressure, or chemistry from as exiting the first outlet valve.

20. The apparatus of claim 19 , wherein the chemical ampoule is a sublimation ampoule, an evaporation ampoule, or a combination thereof.