Method for improving uniformity in deposited low k dielectric material

Abstract

A method for forming a low k dielectric material block is provided. In one example, the method includes depositing a low k dielectric layer over a semiconductor substrate and curing the deposited low k dielectric layer. The curing may be performed using a remote plasma process in which an excitation gas is excited in a selected region remote from the deposited low k dieletric layer to carry radiation energy and transfer to the low k dielectric layer when the excitation gas contacts the low k dielectric layer.

1 . A method for forming a low k dielectric material block comprising: 
 depositing a low k dielectric layer over a semiconductor substrate; and    curing the deposited low k dielectric layer using a remote plasma process in which an excitation gas is excited in a selected region remote from the deposited low k dielectric layer to carry radiation energy and transfer the energy to the low k dielectric layer when the excitation gas contacts the low k dielectric layer.    
     
     
         2 . The method of  claim 1  wherein the curing lasts from approximately thirty seconds to ten minutes.  
     
     
         3 . The method of  claim 1  wherein the curing is completed in Rapid Thermal Processing (RTP) equipment with a radiation source.  
     
     
         4 . The method of  claim 1  wherein the curing occurs at a temperature of approximately 250° C. to 450° C.  
     
     
         5 . The method of  claim 1  wherein the depositing is accomplished using a plasma chemical vapor deposition (CVD) process.  
     
     
         6 . The method of  claim 1  wherein the excitation gas is H2.  
     
     
         7 . The method of  claim 1  wherein the excitation gas is selected from a group consisting of noble gases, CH4, O2, H2, N2O, or a combination thereof.  
     
     
         8 . A method for forming a substantially homogenous layer of dielectric material, the method comprising: 
 depositing a low k dielectric layer over a semiconductor substrate;    exciting a gas in a location remote from the deposited low k dielectric layer; and    directing the excited gas towards the deposited low k dielectric layer, wherein energy contained by the gas operates to cure the low k dielectric layer when the gas contacts the low k dielectric layer.    
     
     
         9 . The method of  claim 8  wherein the curing lasts from approximately thirty seconds to ten minutes.  
     
     
         10 . The method of  claim 8  wherein the curing occurs at a temperature of approximately 250° C. to 450° C.  
     
     
         11 . The method of  claim 8  wherein the depositing is accomplished using a plasma chemical vapor deposition (CVD) process.  
     
     
         12 . The method of  claim 8  wherein the gas is H2.  
     
     
         13 . The method of  claim 8  wherein the gas is selected from a group consisting of noble gases, CH4, O2, H2, N2O, or a combination thereof.  
     
     
         14 . The method of  claim 8  further comprising: 
 creating a trench;  
 creating a via; and  
 depositing a conductive metal into the trench and via.  
 
     
     
         15 . The method of  claim 14  further comprising performing a chemical mechanical planarization process after depositing the conductive metal.  
     
     
         16 . A semiconductor device comprising: 
 a low k dielectric material block having a first low k dielectric layer with a higher density on top of and contiguous to a second low k dielectric layer;    a trench formed in the first low k dielectric layer;    a via formed in the second low k dielectric layer; and    a conductive metal deposited into the trench and the via.    
     
     
         17 . The semiconductor device of  claim 16  wherein at least one of the first and second layers is substantially homogenous.