Enhanced process and profile simulator algorithms

• US 7,139,632 B2
• Filed: 09/01/2004
• Issued: 11/21/2006
• Est. Priority Date: 03/03/1998
• Status: Expired due to Fees

• Current Assignee: Lam Research Corporation
• Original Assignee: Lam Research Corporation
• Inventors: Vahedi, Vahid, Cooperberg, David
• Primary Examiner(s): Picard, Leo
• Assistant Examiner(s): KASENGE, CHARLES R
• Application Number:
  US10/932,926
• Publication Number:
  US 20050278057A1
• Time in Patent Office: 811 Days
• Field of Search: 700/28, 700/30, 700/31, 700/34, 700/47, 700/52, 700/121, 702/85, 702/104, 703/6, 703/13, 703/22, 438/5, 438/9, 438/14, 156/345.24
• US Class Current: 700/121
• CPC Class Codes: H01J 37/321 the radio frequency energy being inductively coupled to the plasma
• CPC Class Codes: H01J 37/32174 Circuits specially adapted for controlling the RF discharge
• CPC Class Codes: H01J 37/32935 Monitoring and controlling tubes by information coming from the object and/or discharge

Abstract

A method for enhancing a process and profile simulator algorithm predicts the surface profile that a given plasma process will create. An energetic particle is first tracked. The ion fluxes produced by the energetic particle are then recorded. A local etch rate and a local deposition rate are computed from neutral fluxes, surface chemical coverage, and surface material type that are solved simultaneously.

Claims

1. A plasma chamber comprising:

a chamber;

a first power supply;

a second power supply;

a gas supply and exhaust;

an inductor on top of said chamber, said inductor coupled to said first power supply;

an electrode inside said chamber, said electrode coupled to said second power supply;

a first power controller coupled to said first power supply;

a second power controller coupled to said second power supply;

a pressure controller coupled to said gas supply and exhaust; and

a computer coupled to said first power controller, said second power controller, said pressure controller,

wherein said computer predictively calculates a surface profile to be created on a substrate by a plasma process sequence,

wherein said computer tracks an energetic particle,

wherein said computer records a plurality of ion fluxes from said energetic particle,

wherein said computer solves simultaneously for a plurality of neutral fluxes, a surface chemical coverage, a surface material type, and

wherein said computer computes a local etch rate and a local deposition rate from said plurality of ion fluxes, said plurality of neutral fluxes, said surface chemical coverage, said surface material type.

2. The plasma chamber of claim 1 wherein said solving simultaneously for said plurality of neutral fluxes, said surface chemical coverage, said surface material type further comprises:

computing a plurality of neutral fluxes;

solving a self-consistent plurality of site balance equations;

calculating an etch rate of a depositing film;

adjusting said surface material type to said depositing film or an underlying material type; and

reiterating said computing, solving, calculating, adjusting until said plurality of neutral fluxes, said surface chemical coverage, and said surface material type are self-consistent with each other.

3. The plasma chamber of claim 2 wherein said computing a plurality of neutral fluxes further comprises:

selecting a neutral specie;

calculating a direct flux distribution for said neutral specie;

calculating a reemission flux for said neutral specie;

computing a transmission matrix for said neutral specie;

solving for neutral fluxes for said neutral specie; and

repeating said selecting, said calculating said direct flux distribution, said calculating said reemission matrix, said computing, said solving another neutral specie until all neutral species have been selected.

4. The plasma chamber of claim 1 further comprising a parallel computer or network of workstations coupled to said computer for distributing a computation of the regression analysis.

5. The plasma chamber of claim 1 wherein said computer tracks said energetic particle using three dimensional coordinates.

6. A method for operating a plasma chamber comprising:

calculating a process surface profile to be created on a substrate by a plasma process sequence; and

processing said substrate according to said plasma process sequence,

wherein said calculating comprises;

tracking an energetic particle;

recording a plurality of ion fluxes from said energetic particle;

solving simultaneously for a plurality of neutral fluxes, a surface chemical coverage, a surface material type; and

computing a local etch rate and a local deposition rate from said plurality of ion fluxes, said plurality of neutral fluxes, said surface chemical coverage, said surface material type.

7. The method of claim 6 wherein said solving simultaneously for said plurality of neutral fluxes, said surface chemical coverage, said surface material type further comprises:

computing a plurality of neutral fluxes;

solving a self-consistent plurality of site balance equations;

calculating an etch rate of a depositing film;

adjusting said surface material type to said depositing film or an underlying material type; and

reiterating said computing, solving, calculating, adjusting until said plurality of neutral fluxes, said surface chemical coverage, and said surface material type are self-consistent with each other.

8. The method of claim 7 wherein said computing said plurality of neutral fluxes further comprises:

selecting a neutral specie;

calculating a direct flux distribution for said neutral specie;

calculating a reemission flux for said neutral specie;

computing a transmission matrix for said neutral specie;

solving for neutral fluxes for said neutral specie; and

repeating said selecting, said calculating said direct flux distribution, said calculating said reemission matrix, said computing, said solving another neutral specie until all neutral species have been selected.

9. The method of claim 6 further comprising:

distributing said solving and computer over a parallel computer or network of workstations.

10. The method of claim 6 further comprising:

tracking said energetic particle using three dimensional coordinates.

11. A plasma chamber comprising:

means for calculating a process surface profile to be created on a substrate by a plasma process sequence, said means for calculating further comprising;

means for tracking an energetic particle;

means for recording a plurality of ion fluxes from said energetic particle;

means for solving simultaneously for a plurality of neutral fluxes, a surface chemical coverage, a surface material type; and

means for computing a local etch rate and a local deposition rate from said plurality of ion fluxes, said plurality of neutral fluxes, said surface chemical coverage, said surface material type; and

means for processing said substrate according to said plasma process sequence.