Enhanced process and profile simulator algorithms

• US 6,804,572 B1
• Filed: 06/30/2000
• Issued: 10/12/2004
• Est. Priority Date: 03/03/1998
• Status: Expired due to Term

• Current Assignee: Lam Research Corporation
• Original Assignee: Lam Research Corporation
• Inventors: Cooperberg, David, Vahedi, Vahid
• Primary Examiner(s): Paladini, Albert W.
• Assistant Examiner(s): Lee, Douglas S.
• Application Number:
  US09/609,593
• Time in Patent Office: 1,565 Days
• Field of Search: 700/29-31, 700/97, 700/103, 700/104, 700/121, 438/8, 438/9, 438/14, 438/16, 438/788, 438/792, 438/798, 703/6, 703/13
• 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 enhances a process and profile simulator algorithm to predict the surface profile that a given plasma process will create. The method first tracks an energetic particle and then records the ion fluxes produced by the energetic particle. 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 method for enhancing a profile simulator algorithm, the method comprising:

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.

2. A method as in claim 1 wherein said solving simultaneously for said plurality of neutral fluxes, said surface chemical coverage, said surface material type further comprising:

computing a plurality of neutral fluxes;

solving a self-consistent plurality of site balance equations;

calculating an etch rate of a depositing film; and

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. A method as in claim 2 wherein 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 method of claim 1 further comprising:

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

5. A method of claim 1 further comprising:

tracking said energetic particle using three dimensional coordinates.

6. A program storage device readable by a machine, tangibly embodying a program of instructions readable by the machine to perform a method for enhancing a profile simulator algorithm, the method comprising:

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. An apparatus for a method for enhancing a profile simulator algorithm, the method 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.