Variable cycle and time rf activation method for film thickness matching in a multi-station deposition system

Abstract

Methods and apparatuses for depositing approximately equal thicknesses of a material on at least two substrates concurrently processed in separate stations of a multi-station deposition apparatus are provided.

What is claimed is: 
     
         1 . A method of depositing approximately equal thicknesses of a material on at least two substrates concurrently processed in separate stations of a multi-station deposition apparatus, the method comprising:
 (a) providing a first substrate in a first station and a second substrate in a second station of the deposition apparatus;   (b) concurrently depositing the material on the first substrate in the first station and on the second substrate in the second station, wherein deposition conditions in the first and second stations are substantially the same, but yet produce a thicker layer of the material on the first substrate in the first station than on the second substrate in the second station;   (c) adjusting the deposition conditions in the first station to slow or stop depositing the material on the first substrate while continuing to deposit the material on the second substrate in the second station under the conditions in (b); and   (d) completing deposition on the first substrate in the first station and the second substrate in the second station such that a total thickness of the material deposited on the first substrate and on the second substrate is substantially equal.   
     
     
         2 . The method of  claim 1 , wherein the deposition conditions comprise exposing the first substrate and the second substrate to a precursor of the material. 
     
     
         3 . The method of  claim 2 , wherein adjusting the deposition conditions comprises reducing or stopping flow of the precursor to the first station. 
     
     
         4 . The method of  claim 1 , wherein the deposition conditions comprise exposing the first substrate and the second substrate to a plasma. 
     
     
         5 . The method of  claim 4 , wherein adjusting the deposition conditions comprises reducing or stopping the exposure of the first substrate to the plasma. 
     
     
         6 . The method of  claim 1 , wherein the first wafer does not move from the first station during (b) and (c). 
     
     
         7 . The method of  claim 1 , wherein (b) comprises a cyclic repetition of (i) precursor dosing to absorb precursor on the first and second substrates, and (ii) exposing the first and second substrates to plasma to cause the precursor to react to form the material. 
     
     
         8 . The method of  claim 7 , wherein (c) comprises stopping the precursor dosing and/or the plasma exposure in the first station to thereby reduce a thickness of the material deposited during the cyclic repetitions, while continuing to conduct the cyclic repetitions on the second substrate in the second station under the conditions in (b). 
     
     
         9 . The method of  claim 7 , wherein (c) comprises adjusting the duration or power of the plasma in the first station to thereby reduce a thickness of the material deposited during the cyclic repetitions, while continuing to conduct the cyclic repetitions on the second substrate in the second station under the conditions in (b). 
     
     
         10 . The method of  claim 1 , further comprising, before or during (b), analyzing measurement information regarding the relative deposition rates in the first and second stations, and using the measurement information to determine how to adjust the deposition conditions in (c). 
     
     
         11 . The method of  claim 10 , wherein the measurement information is obtained during (b). 
     
     
         12 . The method of  claim 1 , further comprising, before or during (b), analyzing measurement information regarding physical characteristics of the first substrate and the second substrate, and using the measurement information to determine how to adjust the deposition conditions in (c). 
     
     
         13 . A method of semiconductor deposition for creating approximately equal thicknesses of a material on at least two substrates concurrently processed in separate stations of a multi-station deposition apparatus, the method comprising:
 (a) providing a first substrate in a first station and a second substrate in a second station of the deposition apparatus;   (b) exposing, at the same time, the first substrate in the first station and the second substrate in the second station to a precursor of the material;   (c) activating, at the same time, a reaction of the precursor on the first substrate in the first station and a reaction of the precursor on the second substrate in the second station;   (d) performing (b) and (c) for N1 cycles, wherein:
 each of the N1 cycles comprises depositing a thin film of substantially equal thickness t 1  of the material on the first substrate and a thin film of substantially equal thickness t 2  of the material on the second substrate, and 
 performing N1 cycles creates a total deposition thickness T 1  of the material on the first substrate and a total deposition thickness T 2 A of the material on the second substrate, wherein T 1  is greater than T 2 A; and 
   (e) exposing the second substrate in the second station to the precursor and activating a reaction of the precursor on the second substrate in the second station for N2 cycles, wherein:
 each of the N2 cycles comprises depositing a thin film of substantially equal thickness t 2  of the material on the second substrate, 
 each of the N2 cycles comprises the first substrate remaining in the first station and slowing or stopping the deposition of a layer of the material on the first substrate, and 
 performing N1 and N2 cycles creates a total deposition thickness T 2  of the material on the second substrate that is substantially equal to T 1 . 
   
     
     
         14 . The method of  claim 13 , wherein:
 the activating in (c) comprises independently providing a plasma in each station for a first plasma time at a first plasma power, and   the activating in (e) comprises independently providing a plasma in the second station.   
     
     
         15 . The method of  claim 14 , wherein:
 the activating in (e) comprises independently providing a plasma in the second station for a second plasma time that is different than the first plasma time, and   the thin film of substantially equal thickness t 2  deposited in each N1 cycle is different than the thin film of substantially equal thickness t 2  deposited in each N2 cycle.   
     
     
         16 . The method of  claim 14 , wherein:
 the activating in (e) comprises independently providing a plasma in the second station at a second plasma power level that is different than the first plasma power level, and   the thin film of substantially equal thickness t 2  deposited in each N1 cycle is different than the thin film of substantially equal thickness t 2  deposited in each N2 cycle.   
     
     
         17 . The method of  claim 13 , wherein:
 the exposing in (c) comprises flowing a precursor for a first exposure time to the first station and the second station,   the exposing in (e) comprises flowing a precursor for a second exposure time to the second station, and   the thin film of substantially equal thickness t 2  deposited in each N1 cycle is different than the thin film of substantially equal thickness t 2  deposited in each N2 cycle.   
     
     
         18 . A multi-station deposition apparatus, the apparatus comprising:
 a vacuum system;   a gas delivery system;   a processing chamber that includes at least two stations, wherein each station shares the vacuum system and the gas delivery system; and   a controller for controlling the multi-station deposition apparatus to deposit approximately equal thicknesses of a material on at least two substrates concurrently processed in separate stations, the controller comprising control logic for:
 (a) providing a first substrate in a first station and a second substrate in a second station of the deposition apparatus, 
 (b) concurrently depositing the material on the first substrate in the first station and on the second substrate in the second station, wherein deposition conditions in the first and second stations are substantially the same, but yet produce a thicker layer of the material on the first substrate in the first station than on the second substrate in the second station, 
 (c) adjusting the deposition conditions in the first station to slow or stop depositing the material on the first substrate while continuing to deposit the material on the second substrate in the second station under the conditions in (b), and 
 (d) completing deposition on the first substrate in the first station and the second substrate in the second station such that a total thickness of the material deposited on the first substrate and on the second substrate is substantially equal. 
   
     
     
         19 . The apparatus of  claim 18 , wherein:
 each station comprises a showerhead to distribute a precursor of the material onto the substrate in that station, and   the gas delivery system is configured to control delivery of the precursor of the material to each station.   
     
     
         20 . The apparatus of  claim 19 , wherein:
 the controller further comprises control logic for independently controlling precursor delivery to each station, and   adjusting the deposition conditions in (c) comprises reducing or stopping flow of the precursor to the first station.   
     
     
         21 . The apparatus of  claim 18 , further comprising a plasma source configured to independently form and maintain a plasma in each station, wherein:
 the controller further comprises control logic for independently forming and maintaining a plasma in each station, and   the deposition conditions in (b) comprise exposing the first substrate and the second substrate to the plasma.   
     
     
         22 . The apparatus of  claim 21 , wherein:
 the controller further comprises control logic for independently controlling a plasma power level in each station, and   adjusting the deposition conditions in (c) comprises reducing or stopping the exposure of the first substrate to the plasma.   
     
     
         23 . The apparatus of  claim 21 , wherein:
 the controller further comprises control logic for independently controlling a plasma time in each station, and   adjusting the deposition conditions in (c) comprises reducing or stopping the exposure of the first substrate to the plasma.