Atomic layer doping apparatus and method

• US 6,746,934 B2
• Filed: 11/22/2002
• Issued: 06/08/2004
• Est. Priority Date: 08/31/2000
• Status: Expired due to Term

• Current Assignee: Micron Technology, Inc.
• Original Assignee: Micron Technology, Inc.
• Inventors: Sandhu, Gurtej, Doan, Trung T.
• Primary Examiner(s): Mulpuri, Savitri
• Application Number:
  US10/301,573
• Publication Number:
  US 20030073318A1
• Time in Patent Office: 564 Days
• Field of Search: 427/255.23, 427/255.26, 427/255.38, 427/255.34, 427/248.1, 118/718, 118/719, 438/478, 438/479, 438/542, 438/558, 438/559, 438/567, 438/565, 438/566, 438/795
• US Class Current: 438/428
• CPC Class Codes: H01L 21/2254 from or through or into an applied layer, e.g. photoresist, nitrides
• CPC Class Codes: H01L 21/67167 surrounding a central transfer chamber
• CPC Class Codes: H01L 21/6719 characterized by the construction of the processing chambers, e.g. modular processing chambers
• CPC Class Codes: H01L 21/67207 comprising a chamber adapted to a particular process
• CPC Class Codes: H01L 21/67213 comprising at least one ion or electron beam chamber coating by ion implantation C23C; ion or electron beam tubes H01J37/00
• CPC Class Codes: H01L 21/67745 characterized by movements or sequence of movements of transfer devices

Abstract

An improved atomic layer doping apparatus is disclosed as having multiple doping regions in which individual monolayer species are first deposited and then dopant atoms contained therein are diffused into the substrate. Each doping region is chemically separated from adjacent doping regions. A loading assembly is programmed to follow pre-defined transfer sequences for moving semiconductor substrates into and out of the respective adjacent doping regions. According to the number of doping regions provided, a plurality of substrates could be simultaneously processed and run through the cycle of doping regions until a desired doping profile is obtained.

Claims

1. A method of operating an atomic layer doping apparatus, said doping apparatus comprising a first doping region and a second doping region, said method comprising the steps of:

positioning a wafer in said first doping region;

introducing a first dopant species into said first doping region and depositing said first dopant species on said wafer as a first atomic monolayer, said first atomic monolayer being deposited by atomic layer deposition;

moving said wafer from said first doping region to said second doping region, said first and second doping regions being separated from one another by an inert gas curtain; and

introducing dopants from said first atomic monolayer into said wafer in said second doping region.

2. The method of claim 1 further comprising the act of annealing said wafer after said act of introducing said dopants into said wafer.

3. The method of claim 1, wherein said act of introducing said dopants into said wafer includes diffusion of said dopants.

4. The method of claim 1, wherein said act of introducing said dopants into said wafer includes contacting said wafer with a non-reactive plasma.

5. The method of claim 1 further comprising the act of moving said wafer back and forth between said first and second doping regions.

6. The method of claim 1 further comprising the act of moving said wafer back to said first doping region and depositing said first dopant species as a second atomic monolayer.

7. The method of claim 1, wherein said first and second doping regions are adjacent to each other.

8. The method of claim 1 further comprising the act of simultaneously processing at least two wafers among said first and second doping regions and depositing a respective dopant species in each of said doping regions.

9. The method of claim 1, wherein said least two wafers are sequentially moved among said first and second doping regions.

10. A method of conducting atomic layer doping comprising the steps of;

depositing a first atomic monolayer including atoms of a dopant species on a substrate in a first doping region, said first atomic monolayer being deposited by atomic layer deposition;

moving said substrate from said first doping region to a second doping region, which is chemically isolated from said first doping region by an inert gas curtain; and

introducing said atoms of said dopant species into said wafer in said second doping region.

11. The method of claim 10, wherein said act of depositing said first monolayer species further comprises introducing a first dopant species into said first doping region.

12. The method of claim 10, wherein said act of introducing said atoms of said dopant species into said wafer further comprises introducing a non-reactive plasma into said second doping region and contacting said non-reactive plasma with said first atomic monolayer species.

13. The method of claim 10, wherein said act of introducing said atoms of said dopant species into said wafer further comprises heating said wafer so that said atoms diffuse into a surface region of said wafer.

14. The method of claim 10 further comprising the act of annealing said wafer.

15. The method of claim 10 further comprising the act of moving said substrate back and forth between said first and second doping regions.

16. The method of claim 10, wherein a plurality of first and second doping regions are provided, and said method further comprising depositing said first monolayer on respective substrates and introducing atoms from said first monolayers into respective substrates in respective pairs of first and second doping regions, said first and second doping regions of each pair being adjacent to one another.

17. The method of claim 16, wherein a plurality of substrates, each of said plurality of substrates residing in respective regions, are moved sequentially from said first doping regions to said second doping regions.