Methods to form electronic devices and methods to form a material over a semiconductive substrate

Abstract

A first electrode and a doped oxide layer laterally proximate thereof are provided over a substrate. A silicon nitride layer is formed over both the doped oxide layer and the first electrode to a thickness of no greater than 80 Angstroms over at least the first electrode by low pressure chemical vapor deposition using feed gases comprising a silicon hydride, H 2 and ammonia. The substrate with silicon nitride layer is exposed to oxidizing conditions comprising at least 700° C. to form a silicon dioxide layer over the silicon nitride layer, with the thickness of silicon nitride over the doped oxide layer being sufficient to shield oxidizable substrate material beneath the doped oxide layer from oxidizing during the exposing. A second electrode is formed over the silicon dioxide layer and the first electrode. In one implementation, the chemical vapor depositing comprises feed gases of a silicon hydride and ammonia, with the depositing comprising increasing internal reactor temperature from below 500° C. to a maximum deposition temperature above 600° C. and starting feed of the silicon hydride into the reactor at a temperature less than or equal to 600° C. In one implementation the depositing comprises increasing internal reactor temperature from below 500° C. to a maximum deposition temperature above 600° C. using a temperature ramp rate of at least 10° C./minute from at least 500° C. to at least 600° C. Other aspects and implementations are described.

1 - 47 . (canceled)  
   
   
       48 . A method of forming a material over a semiconductive substrate comprising: 
 chemical vapor depositing a material over a semiconductive substrate within a reactor using at least one reactant gas while the substrate is rotating; and    reducing rotation rate of the substrate upon substantially ceasing flow of the at least one reactant gas to the reactor.    
   
   
       49 . The method of  claim 48  wherein the chemical vapor depositing comprises low pressure chemical vapor deposition.  
   
   
       50 . The method of  claim 48  wherein the chemical vapor depositing comprises low pressure chemical vapor deposition void of plasma.  
   
   
       51 . The method of  claim 48  wherein the rotation rate is reduced by at least 50% of that immediately prior to substantially ceasing flow of the at least one reactant gas to the reactor.  
   
   
       52 . The method of  claim 48  wherein said reducing is to some constant lower rate which is maintained for at least 1 minute.  
   
   
       53 . The method of  claim 48  wherein flow of all reactant gases fed to the reactor is ceased at substantially the same time.  
   
   
       54 - 59 . (canceled)  
   
   
       60 . A method of forming a material over a semiconductive substrate comprising: 
 chemical vapor depositing a material over a semiconductive substrate within a reactor using at least one reactant gas while the substrate is rotating; and    reducing rotation rate of the substrate within 2 minutes of substantially ceasing flow of the at least one reactant gas to the reactor.    
   
   
       61 . The method of  claim 60  wherein the reducing occurs within 60 seconds of substantially ceasing flow of the at least one reactant gas to the reactor.  
   
   
       62 . The method of  claim 60  wherein the reducing occurs commensurate with or after substantially ceasing flow of the at least one reactant gas to the reactor.  
   
   
       63 . The method of  claim 60  wherein the reducing occurs after substantially ceasing flow of the at least one reactant gas to the reactor.  
   
   
       64 . The method of  claim 60  wherein the reducing occurs before substantially ceasing flow of the at least one reactant gas to the reactor.  
   
   
       65 . The method of  claim 60  wherein the rotation rate is reduced by at least 50% of that immediately prior to starting said reducing.  
   
   
       66 . The method of  claim 60  wherein said reducing is to some constant lower rate which is maintained for at least 1 minute.  
   
   
       67 . The method of  claim 60  wherein the reducing occurs commensurate with or after substantially ceasing flow of the at least one reactant gas to the reactor, and the reducing is to some constant lower rate which is maintained for at least 1 minute.  
   
   
       68 . The method of  claim 60  wherein the reducing occurs after substantially ceasing flow of the at least one reactant gas to the reactor, and the reducing is to some constant lower rate which is maintained for at least 1 minute.  
   
   
       69 - 76 . (canceled)  
   
   
       77 . A method of forming a material over a semiconductive substrate comprising: 
 chemical vapor depositing a material over a semiconductive substrate within a reactor using at least one reactant gas; and    flowing an inert cooling gas through the reactor to cool the substrate and deposited material.    
   
   
       78 . The method of  claim 77  wherein pressure within the reactor during the cooling is greater than 1 atmosphere.  
   
   
       79 . The method of  claim 77  wherein the chemical vapor depositing is low pressure chemical vapor deposition.  
   
   
       80 . The method of  claim 77  wherein the chemical vapor depositing is low pressure chemical vapor deposition, and pressure within the reactor during the cooling is greater than 1 atmosphere.  
   
   
       81 - 89 . (canceled)