Microelectronic device drying devices and techniques
View Patent ↗Improved methods of rinsing and drying microelectronic devices by way of an immersion processing apparatus are provided for effectively cleaning microelectronic devices. Methods and arrangements control the separation of one or more microelectronic devices from a liquid environment as part of a replacement of the liquid environment with a gas environment. Cleaning enhancement substance, such as IPA, is introduced into the gas environment according to a controlled profile while the separation step is conducted. The controlled profile being directed to the timing of introduction of cleaning enhancement substance, the concentration of cleaning enhancement substance and/or flow rates thereof into the vessel. Controlled timing of gas and cleaning enhancement substance delivery can also improve effectiveness of separation. Methods and arrangements are also provided for controlling a drying step to be conducted on the one or more microelectronic devices after they have been separated from a liquid environment by replacing the liquid environment with a gas environment. Preferably, an arrangement of gas distribution devices create one or more drying gas curtains, which gas curtains may be controllably directed with respect to a set of microelectronic devices to provide optimal drying of the microelectronic devices after being separating from a liquid.
1. A method for processing at least one microelectronic device comprising:
immersing at least a portion of at least one microelectronic device into a liquid bath provided within a vessel for performing a treatment on at least the immersed portion thereof;
separating the microelectronic device from the liquid bath by replacing said liquid with a gas environment adjacent to at least a surface portion of the microelectronic device; and
delivering a cleaning enhancement substance during said replacing, said cleaning enhancement substance causing a concentration gradient of said cleaning enhancement substance in liquid at an interface between the surface of the microelectronic device and the liquid bath to enhance fluid flow from the microelectronic device surface,
wherein the delivery of the cleaning enhancement substance is varied from a first stage to a second stage during said replacing step by changing a flow rate of delivery of cleaning enhancement substance from a first predetermined flow rate during the first stage to a second predetermined flow rate during the second stage.
2. The method of claim 1 , wherein delivery of cleaning enhancement substance is further varied to at least a third stage by changing a flow rate of delivery of cleaning enhancement substance from the second flow rate to a third flow rate.
3. The method of claim 1 , wherein the cleaning enhancement substance is delivered into the vessel at a substantially even concentration of between 0.5 percent and 3.6 percent within a carrier gas.
4. The method of claim 1 , wherein at least one flow rate is varied by increasing the flow rate.
5. The method of claim 3 , wherein the cleaning enhancement substance comprises IPA and the carrier gas comprises nitrogen.
6. The method of claim 4 , wherein the separation is performed by lowering the liquid level within the vessel.
7. The method of claim 6 , wherein the liquid level is lowered below the at least one microelectronic device and the delivery of cleaning enhancement substance is continued while the liquid level is lowered further.
8. The method of claim 7 , wherein a quick dump of remaining liquid is conducted at a point after the liquid level is lowered below the at least one microelectronic device while the cleaning enhancement substance is delivered.
9. The method of claim 8 , further comprising a step of drying the at least one microelectronic device by supplying at least one gas stream directed within the vessel to dry a surface of the at least one microelectronic device, and wherein delivery of cleaning enhancement substance is continued for at least an initial portion of the drying step.