Substrate processing appartus and standby method for ejection head

Abstract

In a substrate processing apparatus, an ejection surface of an ejection head located at a standby position is immersed in an immersion liquid retained in a reservoir during standby of the ejection head. This prevents drying of a plurality of outlets provided in the ejection head and drying of processing liquid flow passages that communicate with the outlets. It is thus possible to suppress or prevent clogging of the fine outlets. When the ejection head resumes processing on a substrate, the immersion liquid in the reservoir is discharged and then a liquid removing part removes the immersion liquid adhering to the ejection surface. Accordingly, it is possible to prevent the immersion liquid remaining on the ejection surface from dropping and adhering to the substrate (so-called “liquid dripping”) when, for example, the ejection head is moved to a position above the substrate.

1 . A substrate processing apparatus for processing a substrate, comprising:
 a substrate holding part for holding a substrate;   a cup part surrounding said substrate holding part;   an ejection head disposed inside said cup part and above said substrate holding part and for ejecting a processing liquid toward said substrate from an outlet provided in an ejection surface;   a supply part movement mechanism for moving said ejection head from a position above said substrate holding part to a standby position outside said cup part;   a reservoir disposed outside said cup part and for retaining an immersion liquid in which said ejection surface of said ejection head located at said standby position is immersed; and   a liquid removing part for removing said immersion liquid from said ejection surface.   
     
     
         2 . The substrate processing apparatus according to  claim 1 , wherein
 said supply part movement mechanism causes relative movement of said ejection head and said reservoir in a direction that said ejection head and said reservoir become closer to each other to immerse said ejection surface of said ejection head in said immersion liquid retained in said reservoir,   said ejection surface is separated from said immersion liquid either by discharging said immersion liquid from said reservoir or by said supply part movement mechanism causing relative movement of said ejection head and said reservoir in a direction that said ejection head and said reservoir become away from each other, and   after said ejection surface is separated from said immersion liquid, said liquid removing part removes said immersion liquid that remains on said ejection surface.   
     
     
         3 . The substrate processing apparatus according to  claim 1 , wherein
 said processing liquid is continuously or intermittently ejected from said outlet in a state where said ejection surface is immersed in said immersion liquid.   
     
     
         4 . The substrate processing apparatus according to  claim 3 , wherein
 said immersion liquid is continuously or intermittently supplied and discharged into and from said reservoir in a state where said ejection surface is immersed in said immersion liquid.   
     
     
         5 . The substrate processing apparatus according to  claim 4 , wherein
 said immersion liquid is supplied from a bottom of said reservoir and discharged from a top of said reservoir.   
     
     
         6 . The substrate processing apparatus according to  claim 3 , wherein
 the ejection of said processing liquid from said outlet is stopped before said ejection surface is separated from said immersion liquid.   
     
     
         7 . The substrate processing apparatus according to  claim 6 , wherein
 said immersion liquid is continuously or intermittently supplied and discharged into and from said reservoir in a state where said ejection surface is immersed in said immersion liquid.   
     
     
         8 . The substrate processing apparatus according to  claim 7 , wherein
 said immersion liquid is supplied from a bottom of said reservoir and discharged from a top of said reservoir.   
     
     
         9 . The substrate processing apparatus according to  claim 1 , wherein
 said liquid removing part is a gas emitting part for emitting gas toward said ejection head.   
     
     
         10 . The substrate processing apparatus according to  claim 9 , wherein
 said liquid removing part emits said gas toward said ejection head inside said reservoir.   
     
     
         11 . The substrate processing apparatus according to  claim 10 , wherein
 said reservoir is provided with a lid part for covering a top of said reservoir,   said lid part having an insertion opening through which a lower end portion of said ejection head is inserted.   
     
     
         12 . The substrate processing apparatus according to  claim 9 , wherein
 said liquid removing part emits said gas in a direction away from said substrate holding part.   
     
     
         13 . The substrate processing apparatus according to  claim 1 , wherein
 said immersion liquid is continuously or intermittently supplied and discharged into and from said reservoir in a state where said ejection surface is immersed in said immersion liquid.   
     
     
         14 . The substrate processing apparatus according to  claim 13 , wherein
 said immersion liquid is supplied from a bottom of said reservoir and discharged from a top of said reservoir.   
     
     
         15 . The substrate processing apparatus according to  claim 1 , wherein
 said ejection head includes:   a head body part having an outer surface, part of which is said ejection surface, and for holding said processing liquid therein; and   a piezoelectric element attached to said head body part and for vibrating said processing liquid held in said head body part to cause the ejection of said processing liquid from said outlet, and   said piezoelectric element is driven to vibrate said immersion liquid retained in said reservoir in a state where said ejection surface is immersed in said immersion liquid.   
     
     
         16 . The substrate processing apparatus according to  claim 1 , wherein
 said immersion liquid is the same type of liquid as said processing liquid.   
     
     
         17 . The substrate processing apparatus according to  claim 1 , wherein
 said ejection surface is formed of a lyophilic material having a high affinity for said immersion liquid.   
     
     
         18 . The substrate processing apparatus according to  claim 1 , wherein
 said substrate is cleaned with said processing liquid ejected from said ejection head toward said substrate.   
     
     
         19 . A standby method for an ejection head, said standby method being a method of placing said ejection head of a substrate processing apparatus on standby, said ejection head being disposed inside a cup part and above a substrate holding part surrounded by said cup part and being configured to eject a processing liquid from an outlet provided in an ejection surface toward a substrate held by said substrate holding part,
 said standby method comprising:   a) moving said ejection head from a position inside said cup part to a position outside said cup part;   b) causing relative movement of said ejection head and a reservoir in which an immersion liquid is retained, in a direction that said ejection head and said reservoir become closer to each other to immerse said ejection surface of said ejection head in said immersion liquid;   c) separating said ejection surface from said immersion liquid either by discharging said immersion liquid from said reservoir or by causing relative movement of said ejection head and said reservoir in a direction that said ejection head and said reservoir become away from each other;   d) removing said immersion liquid that remains on said ejection surface; and   e) moving said ejection head to a position inside said cup part.