Dispense nozzle with a shielding device

Abstract

Provided is a nozzle system for dispensing a dispense chemical onto a substrate, the system comprising: a nozzle comprising a nozzle body and a nozzle tip; a shielding device coupled to the nozzle tip, the shielding device configured to create a mini-environment for a dispense chemical such that a partial pressure of the dispense chemical is maintained in the shielding device; wherein the nozzle system is configured to meet selected dispense objectives.

What is claimed is: 
     
         1 . A nozzle system coupled to a semiconductor fabrication system, the nozzle system comprising:
 a dispense chemical supply line;   a nozzle coupled to the dispense chemical supply line, the nozzle comprising a nozzle body and nozzle tip, the nozzle tip coupled to the nozzle body and configured to dispense the dispense chemical onto the substrate;   a nozzle valve coupled to the nozzle body and the dispense chemical supply line, the nozzle valve having an opening and closing rate; and   a shroud coupled to the nozzle tip and configured to create a mini-environment for the dispense chemical such that a partial pressure of the dispense chemical is maintained in the nozzle shroud, the shroud having a shroud volume, shroud wall thickness, and shroud inner wall diameter, the nozzle tip having a dispense area;   wherein the nozzle system is configured to meet selected dispense objectives.   
     
     
         2 . The nozzle system of  claim 1  wherein the selected dispense objectives include the nozzle valve meeting a nozzle valve opening and closing rate that enables the nozzle tip to avoid dripping of the dispense chemical after completion of a dispense operation, no particle contamination of the substrate, and/or lower cost of ownership. 
     
     
         3 . The nozzle system of  claim 1  wherein the selected dispense objectives include controlling the dispense chemical partial pressure in the shroud volume to an acceptable range. 
     
     
         4 . The nozzle system of  claim 1  wherein the dispense chemical includes a resist, a solvent, or one or more semiconductor chemicals. 
     
     
         5 . The nozzle system of  claim 1  further comprising a tray partially filled with a tray chemical wherein the nozzle with the shroud is placed immediately above the tray chemical when the nozzle system is not in use. 
     
     
         6 . The nozzle system of  claim 1  wherein if the nozzle is not dispensing the dispense chemical, the dispense area of the nozzle tip is minimized in order to keep the dispense chemical at the nozzle tip as flat as possible. 
     
     
         7 . The nozzle system of  claim 1  wherein the dispense chemical is held in place in the dispense area by surface tension in the dispense chemical. 
     
     
         8 . The nozzle system of  claim 1  wherein partial pressure of the dispense chemical is a function of the shroud wall thickness and shroud inner wall diameter. 
     
     
         9 . The nozzle system of  claim 1  wherein partial pressure of the dispense chemical is controlled in the shroud by disposing the nozzle in a tray containing a tray chemical close to but not touching the tray chemical. 
     
     
         10 . The nozzle system of  claim 9  wherein disposing the nozzle in the tray minimizes a rate of evaporation of the dispense chemical into the shroud and minimizes a diffusion of the dispense chemical out of the shroud. 
     
     
         11 . The nozzle system of  claim 1   wherein the rate of nozzle valve opening and closing are a function of the viscosity and flow characteristics of the dispense chemical; or   wherein when the dispense chemical is flowing, the dispense chemical flows out of the internal opening of the nozzle and wherein the dispense chemical does not touch the wall of the shroud.   
     
     
         12 . The nozzle system of  claim 1  further comprising a controller configured to control dispense operating variables including flow rate of the dispense chemical, partial pressure of the dispense chemical inside the shroud volume, and temperature of the shroud volume in order to meet the dispense objectives. 
     
     
         13 . A nozzle system for dispensing a dispense chemical onto a substrate, the system comprising:
 a nozzle comprising a nozzle body and a nozzle tip;   a shielding device coupled to the nozzle tip, the shielding device configured to create a mini-environment for a dispense chemical such that a partial pressure of the dispense chemical is maintained in the shielding device;   wherein the nozzle system is configured to meet selected dispense objectives.   
     
     
         14 . The nozzle system of  claim 13  wherein the shielding device is a nozzle shroud. 
     
     
         15 . The nozzle system of  claim 13  wherein the shielding device is a gas shield. 
     
     
         16 . The nozzle system of  claim 13  wherein the shielding device is a nozzle shroud and/or a gas shield. 
     
     
         17 . The nozzle system of  claim 15  wherein the nozzle system further comprises a gas shield generator coupled to the nozzle system and configured to generate the gas shield comprising a shield gas flow to a shielded zone proximate the nozzle tip. 
     
     
         18 . The nozzle system of  claim 15  wherein the nozzle comprises a plurality of nozzles in a nozzle bank. 
     
     
         19 . The nozzle system of  claim 18  wherein the gas flow to the shielded zone is at a velocity higher than a speed of diffusion of reactive gases, the gas flow causing termination of dispense chemical evaporation. 
     
     
         20 . The nozzle system of  claim 15  further comprising a controller configured to utilize selected operating variables which are concurrently controlled to achieve dispense objectives, the dispense objectives comprising cost of ownership, throughput substrates per hour, reduced particle contamination, and reduced usage of the dispense chemical. 
     
     
         21 . A method of controlling a dispense nozzle with a shroud in processing a substrate, the method comprising:
 providing a nozzle system coupled to a fabrication system, the nozzle system comprising a nozzle body, a nozzle valve, a nozzle tip, and a nozzle shroud;   providing a substrate to be processed inside the processing chamber of the fabrication system;   starting dispense of the dispense chemical by opening the nozzle valve to flow the dispense chemical onto a substrate in a processing chamber of the fabrication system;   stopping dispense of the dispense chemical by closing the nozzle valve to stop the flow of the dispense chemical;   controlling, using a controller, the starting dispense and stopping dispense of the dispense chemical in order to achieve one or more dispense objectives.   
     
     
         22 . The method of  claim 21  wherein the one or more nozzle dispensing objectives include no dripping of the dispense chemical after the nozzle valve is closed and wherein partial pressure of the dispense chemical in the nozzle shroud area is kept within a range by controlling a mini-environment of the nozzle shroud. 
     
     
         23 . The method of  claim 21  wherein one or more nozzle dispense objectives includes the opening and closing rate of the nozzle valve is controlled to be able to handle the viscosity and other fluid characteristics of the dispense chemical. 
     
     
         24 . A method of controlling a dispense nozzle with a shielding device in processing a structure on a substrate, the method comprising:
 providing a nozzle system coupled to a fabrication system, the nozzle system comprising a nozzle body, a nozzle valve, a nozzle tip, and a shielding device;   providing a substrate to be processed inside a processing chamber of the fabrication system;   starting dispense of a dispense chemical by opening the nozzle valve to flow the dispense chemical onto a substrate in the processing chamber of the fabrication system;   stopping dispense of the dispense chemical by closing the nozzle valve to stop the flow of the dispense chemical;   controlling, using a controller, dispensing of the dispense chemical in order to achieve one or more dispense objectives.   
     
     
         25 . The method of  claim 24  wherein the one or more dispense objectives include no dripping of the dispense chemical after the nozzle valve is closed and partial pressure of the dispense chemical in the nozzle shroud area is kept within a range by controlling the mini-environment of the nozzle shroud. 
     
     
         26 . The method of  claim 24  wherein one or more dispensing objectives includes an opening and closing rate of the nozzle valve is controlled to be able to handle the viscosity and other fluid characteristics of the dispense chemical. 
     
     
         27 . The method of  claim 24  wherein the shielding device is a nozzle shroud, a gas shield, or a combination of a nozzle shroud and a gas shield.