Adhesion between carbon doped oxide and etch stop layers

Abstract

The invention forms a graded modified layer in a substrate by exposing the substrate to hydrogen plasma. Methyl groups may be removed from carbon doped oxide in the substrate by the hydrogen plasma treatment. This may result in a stronger interface between the substrate and an etch stop layer on the substrate.

1 . A method, comprising: 
 forming a substrate with a top surface;    exposing the top surface of the substrate to hydrogen plasma to remove methyl groups from the top surface; and    depositing an intermediate layer on the top surface of the substrate.    
   
   
       2 . The method of  claim 1 , wherein the intermediate layer comprises at least one of an etch stop layer and a diffusion barrier layer.  
   
   
       3 . The method of  claim 2 , wherein the intermediate layer comprises at ieast one of SiN, SiON and SiC.  
   
   
       4 . The method of  claim 2 , wherein the substrate comprises at least one of carbon doped oxide, a spin on dielectric layer, and porous carbon doped oxide that includes the methyl groups.  
   
   
       5 . The method of  claim 4 , wherein exposing the top surface of the substrate to hydrogen plasma to remove methyl groups comprises: 
 disposing the substrate within a plasma chamber;    exposing the substrate to a flow of hydrogen into the plasma chamber; and    applying a radio frequency power for a selected time.    
   
   
       6 . The method of  claim 5 , wherein the substrate is part of a wafer with a diameter of about 300 mm, and wherein the radio frequency power has a range from about 200 Watts to about 1000 Watts.  
   
   
       7 . The method of  claim 5 , wherein the substrate is part of a wafer with a diameter of about 300 mm, and wherein the radio frequency power has a range from about 400 Watts to about 600 Watts for a 300 mm wafer.  
   
   
       8 . The method of  claim 5 , wherein the selected time is in a range from about 4 seconds to about 30 seconds.  
   
   
       9 . The method of  claim 5 , wherein the selected time is in a range from about 10 seconds to about 15 seconds.  
   
   
       10 . The method of  claim 5 , wherein the substrate is exposed to hydrogen plasma at a temperature in a range from about 200 degrees Celsius to about 450 degrees Celsius.  
   
   
       11 . The method of  claim 5 , wherein the flow of hydrogen into the plasma chamber has a flow rate in a range of about 0.1 liter per minute to about 10 liters per minute.  
   
   
       12 . The method of  claim 5 , wherein the substrate is exposed to hydrogen plasma at a pressure in a range from about 1 Torr to about 10 Torr.  
   
   
       13 . The method of  claim 5 , wherein the substrate is exposed to hydrogen plasma at a pressure in a range from about 2 Torr to about 5 Torr.  
   
   
       14 . The method of  claim 1 , wherein exposing the top surface of the substrate to hydrogen plasma results in a graded modified region of reduced methyl groups with fewer methyl groups at the top surface of the substrate.  
   
   
       15 . The method of  claim 14 , wherein the graded modified region extends less than about 100 angstroms below the top surface of the substrate.  
   
   
       16 . The method of  claim 14 , wherein the graded modified region extends less than about 50 angstroms below the top surface of the substrate.  
   
   
       17 . A device, comprising: 
 a substrate with a top surface;    a graded region of the substrate starting at the top surface of the substrate and extending a distance into the substrate, the graded region having fewer methyl groups at the top surface of the substrate and more methyl groups further into the substrate; and    an intermediate layer on the top surface of the substrate.    
   
   
       18 . The device of  claim 17 , wherein the graded region extends less than about 100 angstroms below the top surface of the substrate.  
   
   
       19 . The device of  claim 17 , wherein the graded region extends less than about 50 angstroms below the top surface of the substrate.  
   
   
       20 . The device of  claim 17 , wherein the intermediate layer comprises at least one of an etch stop layer and a diffusion barrier layer.  
   
   
       21 . The device of  claim 20 , wherein the intermediate layer comprises at least one of SiN, SiON and SiC.  
   
   
       22 . The device of  claim 21 , wherein the substrate comprises at least one of carbon doped oxide, spin on dielectric, and porous carbon doped oxide that includes the methyl groups.  
   
   
       23 . The device of  claim 17 , further comprising an interlayer dielectric layer.  
   
   
       24 . The device of  claim 17 , further comprising: 
 an interlayer dielectric layer;    a via extending from the substrate through the intermediate layer and the interlayer dielectric layer;    a connector electrically connected to the via; and    a package electrically connected to the connector.    
   
   
       25 . A method, comprising: 
 forming a first layer comprising carbon doped oxide;    exposing the carbon doped oxide to hydrogen plasma to remove methyl groups from the carbon doped oxide; and    depositing a second layer comprising at least one of SiN and SiC on the first layer.    
   
   
       26 . The method of  claim 25 , wherein exposing the carbon doped oxide to hydrogen plasma comprises: 
 disposing the carbon doped oxide within a plasma chamber;    flowing hydrogen into the chamber at a rate of about 1 liter per minute;    heating the carbon doped oxide to a temperature in a range of about 200 degrees Celsius to about 450 degrees Celsius; and    applying a radio frequency power in a range from about 400 Watts to about 600 Watts for a time in a range from about 10 seconds to about 15 seconds.