System and method for control of electromagnetic radiation in pecvd discharge processes

Abstract

A system and method for coating a substrate with a film is described. One embodiment includes a process that provides a substrate on which to deposit a film; generates a plasma to produce radicals from a support gas; produces the radicals from the support gas; disassociates a precursor gas using the radicals; deposits material from the disassociated precursor gas on the substrate; and controls the amount of electromagnetic radiation to which the deposited material is exposed.

1 . A method for coating a substrate with a film, the method comprising:
 providing a substrate on which to deposit a film;   generating a plasma to produce radicals from a support gas;   producing the radicals from the support gas;   disassociating a precursor gas using the radicals;   depositing material from the disassociated precursor gas on the substrate; and   controlling the amount of electromagnetic radiation to which the deposited material is exposed.   
     
     
         2 . The method of  claim 1 , wherein controlling the amount of electromagnetic radiation to which the deposited material is exposed comprises:
 blocking ultraviolet radiation emitted by the plasma.   
     
     
         3 . The method of  claim 1 , wherein controlling the amount of electromagnetic radiation to which the deposited material is exposed comprises:
 reducing an aperture opening between the plasma and the deposited material.   
     
     
         4 . The method of  claim 1 , wherein controlling the amount of electromagnetic radiation to which the deposited material is exposed comprises:
 increasing ultraviolet radiation generated.   
     
     
         5 . The method of  claim 1 , wherein generating a plasma to produce radicals from a support gas comprises:
 providing a power signal to generate the plasma.   
     
     
         6 . The method of  claim 5 , wherein providing a power signal to generate the plasma comprises:
 spiking the power signal to thereby increase the amount of ultraviolet radiation.   
     
     
         7 . The method of  claim 6 , wherein spiking the power signal to thereby increase the amount of ultraviolet radiation comprises:
 controlling the timing of spiking the power signal to thereby control the increase in the amount of ultraviolet radiation.   
     
     
         8 . The method of  claim 1 , wherein providing a power signal to generate the plasma comprises:
 varying the power signal to thereby increase the amount of ultraviolet radiation.   
     
     
         9 . The method of  claim 1 , wherein providing a power signal to generate the plasma comprises:
 varying the power signal to thereby vary the wavelength of the ultraviolet radiation.   
     
     
         10 . The method of  claim 1 , wherein controlling the amount of electromagnetic radiation to which the deposited material is exposed comprises:
 varying the amount of ultraviolet radiation to which the deposited material is exposed in accordance with the density of radicals.   
     
     
         11 . The method of  claim 10 , wherein varying the amount of ultraviolet radiation to which the deposited material is exposed comprises:
 increasing the amount of ultraviolet radiation to which the deposited material is exposed when the density of radicals is reduced.   
     
     
         12 . The method of  claim 10 , wherein varying the amount of ultraviolet radiation to which the deposited material is exposed comprises:
 decreasing the amount of ultraviolet radiation to which the deposited material is exposed when the density of radicals is increased.   
     
     
         13 . The method of  claim 8 , wherein controlling the amount of electromagnetic radiation to which the deposited material is exposed comprises:
 varying the amount of ultraviolet radiation to which the deposited material is exposed in accordance with variations to a power signal used to produce the plasma.   
     
     
         14 . A PECVD system comprising:
 a plasma chamber;   an antenna;   a substrate support;   a electromagnetic radiation restrictor positioned between the antenna and the substrate support, the restrictor having a controllable aperture; and   a controller configured to control the controllable aperture.   
     
     
         15 . The PECVD system of  claim 14 , wherein the controller comprises:
 a computer configured to vary the size of the aperture according to at least one PECVD process parameter.   
     
     
         16 . The PECVD system of  claim 14 , wherein the controller comprises:
 a computer configured to vary the size of the aperture according to a density of radicals produced in the plasma chamber.   
     
     
         17 . The PECVD system of  claim 14 , wherein the controller comprises:
 a computer configured to vary the size of the aperture according to variations in a power signal applied to the antenna.   
     
     
         18 . A method of producing a film, the method comprising:
 initiating a PECVD process to deposit a film on a substrate; and   varying the amount of ultraviolet radiation to which the film is exposed during growth.   
     
     
         19 . The method of  claim 18 , wherein varying the amount of ultraviolet radiation to which the film is exposed during growth comprises:
 mechanically varying the amount of ultraviolet radiation to which the film is exposed during growth.   
     
     
         20 . The method of  claim 18 , wherein varying the amount of ultraviolet radiation to which the film is exposed during growth comprises and wherein a plasma used during the PECVD process generates a first amount ultraviolet radiation comprises:
 blocking a first portion of the first amount of ultraviolet radiation from reaching the film.   
     
     
         21 . The method of  claim 20 , wherein varying the amount of ultraviolet radiation to which the film is exposed during growth comprises and wherein a plasma used during the PECVD process generates a first amount ultraviolet radiation:
 blocking less than the first portion of the first amount of ultraviolet radiation blocked from reaching the film.   
     
     
         22 . The method of  claim 18 , wherein varying the amount of ultraviolet radiation to which the film is exposed during growth comprises:
 varying the amount of ultraviolet radiation to which the film is exposed during growth by contouring a power waveform used to drive the PECVD process.   
     
     
         23 . A method of producing a film, the method comprising:
 initiating a PECVD process to deposit a film on a substrate;   generating ultraviolet radiation, wherein the film is exposed to the ultraviolet radiation;   varying the wavelength of the ultraviolet radiation.   
     
     
         24 . The method of  claim 23 , wherein varying the wavelength of the ultraviolet radiation comprises:
 contouring a power waveform used to drive the PECVD process.