Device for etching rinsing and drying substrates in an ultra-clean atmosphere

Abstract

An etching, rinsing and drying device for substrates ( 7 ) comprises a tank ( 5 ) having a diffusing bottom ( 9 ) and an overflow chute ( 2 ). Projection nozzles ( 10, 11 ) are arranged in the diffusing bottom ( 9 ) so as to inject an etching liquid LG and a rinsing liquid LR into the tank. The tank ( 5 ) is equipped at the top part with at least one injection manifold ( 1 ) of a drying liquid LS to form a superficial layer of uniform thickness above the water constituting the rinsing liquid LR. The drying liquid LS is immiscible in water and presents a lower surface tension and density than those of water.

1 - 10 . (Canceled)  
   
   
       11 . Etching, rinsing and drying device for substrates comprising: 
 a tank having a bottom part and a top part with a diffusing bottom at the bottom part and an overflow chute at the top part,    projection nozzles arranged in the diffusing bottom and connected to independent feed systems for injection of an etching liquid LG and a rinsing liquid LR,    at least one deflector situated in proximity of the overflow chute to divert rising flows of liquid,    and means for circulation of the different liquids in the tank,    wherein the tank is equipped at the top part with at least one injection manifold for injecting a drying liquid LS to form a superficial layer of uniform thickness above the water constituting the rinsing liquid LR, said drying liquid LS being immiscible in water and presenting a lower surface tension and density than those of water.    
   
   
       12 . Etching, rinsing and drying device according to  claim 11 , wherein the etching liquid LG is constituted by hydrofluoric acid.  
   
   
       13 . Etching, rinsing and drying device according to  claim 11 , wherein the drying liquid LG is constituted by isopentane.  
   
   
       14 . Etching, rinsing and drying device according to  claim 11 , wherein the overflow chute is equipped with a series of orifices and recovery valves specific to each of the etching LG, rinsing LR and drying LS liquids.  
   
   
       15 . Etching, rinsing and drying device according to  claim 11 , wherein it comprises a reprocessing circuit for the etching liquid LG, rinsing liquid LR and drying liquid LS, enabling the liquids to be purified and filtered for recycling.  
   
   
       16 . Etching, rinsing and drying device according to  claim 11 , wherein it comprises means for reversing the flow due to an hydraulic piston effect generated by the feed system of the bottom connected to the nozzle system in central position, so as to expel the liquid in the ascending direction to the overflow chute and to perform replacement of this liquid by an identical liquid in the case of several cycles when the etching and rinsing stage is performed, or by a different liquid in the case of replacement of the liquid between the etching, cleaning and rinsing stages.  
   
   
       17 . Etching, rinsing and drying device according to  claim 11 , wherein it comprises a common drainage system of the liquid contained in the tank, and means enabling the drainage rate to be controlled.  
   
   
       18 . Etching, rinsing and drying device according to  claim 11 , wherein drying of the substrates is performed by passing a basket containing the substrates through a layer of drying liquid LS after drainage of the liquids contained in the tank has been performed.  
   
   
       19 . Etching, rinsing and drying device according to  claim 11 , wherein drying of the substrates is performed by removing a basket upwards making the substrates pass through the superficial layer of drying liquid LS.  
   
   
       20 . Etching, rinsing and drying device according to  claim 11 , wherein the substrates housed in a basket remain permanently in a liquid medium, as they are immersed in the etching liquid LG until the end of the drying state.