METHOD OF THERMAL PROCESSING STRUCTURES FORMED ON A SUBSTRATE

• US 20070218644A1
• Filed: 07/25/2006
• Published: 09/20/2007
• Est. Priority Date: 03/08/2006
• Status: Active Grant

• Current Assignee: Applied Materials Incorporated
• Original Assignee: Applied Materials Incorporated
• Inventors: Yam, Mark, Moffatt, Stephen, Balakrishna, Ajit, Mayur, Abhilash J., Jennings, Dean, Carey, Paul, Schaffer, William
• Granted Patent: US 7,569,463 B2
• Time in Patent Office: Days
• US Class Current: 438/420
• CPC Class Codes: H01L 21/26506 in group IV semiconductors
• CPC Class Codes: H01L 21/26513 of electrically active species
• CPC Class Codes: H01L 21/268 using electromagnetic radiation, e.g. laser radiation
• CPC Class Codes: H01L 21/324 Thermal treatment for modifying the properties of semiconductor bodies, e.g. annealing, sintering H01L21/20 - H01L21/288 and H01L21/302 - H01L21/322 take precedence
• CPC Class Codes: H01L 21/67115 mainly by radiation
• CPC Class Codes: H01L 21/823418 with a particular manufacturing method of the source or drain structures, e.g. specific source or drain implants or silicided source or drain structures or raised source or drain structures
• CPC Class Codes: H01L 29/0653 adjoining the input or output region of a field-effect device, e.g. the source or drain region
• CPC Class Codes: H01L 29/6659 with both lightly doped source and drain extensions and source and drain self-aligned to the sides of the gate, e.g. lightly doped drain [LDD] MOSFET, double diffused drain [DDD] MOSFET
• CPC Class Codes: H01L 29/66659 with asymmetry in the channel direction, e.g. lateral high-voltage MISFETs with drain offset region, extended drain MISFETs

Abstract

The present invention generally describes one or more apparatuses and various methods that are used to perform an annealing process on desired regions of a substrate. In one embodiment, an amount of energy is delivered to the surface of the substrate to preferentially melt certain desired regions of the substrate to remove unwanted damage created from prior processing steps (e.g., crystal damage from implant processes), more evenly distribute dopants in various regions of the substrate, and/or activate various regions of the substrate. The preferential melting processes will allow more uniform distribution of the dopants in the melted region, due to the increased diffusion rate and solubility of the dopant atoms in the molten region of the substrate. The creation of a melted region thus allows: 1) the dopant atoms to redistribute more uniformly, 2) defects created in prior processing steps to be removed, and 3) regions that have hyper-abrupt dopant concentrations to be formed.

Claims

1. A method of thermally processing a substrate, comprising:

modifying one or more regions in a substrate formed from a first material by disposing a second material within the one or more regions, wherein modifying one or more regions in a substrate with the second material is adapted to lower the melting point of the first material contained within the one or more regions;

disposing a third material within the one or more regions in the substrate; and

delivering an amount of electromagnetic energy to a surface of a substrate which is in thermal communication with the one or more regions, wherein the amount of electromagnetic energy is adapted to cause the first material within the one or more regions to melt.

2. The method of claim 1, further comprising positioning the substrate so that it is in thermal communication with a heat exchanging device, wherein the heat exchanging device is adapted to heat the substrate to a temperature about 20°

C. and about 600°

C.

3. The method of claim 1, further comprising positioning the substrate so that it is in thermal communication with a heat exchanging device, wherein the heat exchanging device is adapted to cool the substrate to a temperature about −

240°

C. and about 20°

C.

4. The method of claim 1, wherein the first material is selected from a group consisting of silicon, germanium, gallium arsenide, gallium phosphide, and gallium nitride.

5. The method of claim 1, wherein the first material is a silicon containing material and the second material is selected from a group consisting of germanium, arsenic, gallium, carbon, tin, and antimony.

6. The method of claim 1, wherein the third material is selected from a group consisting of arsenic, phosphorus, antimony, boron, aluminum, and indium.

7. The method of claim 1, wherein the second material is selected from a group consisting of argon, krypton, xenon and nitrogen.

8. A method of thermally processing a substrate, comprising:

providing a substrate that has one or more first regions that have been modified so that the melting point of the material contained within each of the first regions melts at a lower temperature than the material contained within a second region of the substrate, wherein the second region and each of the first regions are generally adjacent to a surface of the substrate;

depositing a coating over the surface of the substrate, wherein the coating has a different absorption and reflection coefficient than that surface of the substrate;

removing a portion of the coating from the surface of the substrate that is generally adjacent to each of the first regions or the second region; and

delivering an amount of electromagnetic energy to an area on the surface of the substrate that contains the one or more first regions and the second region, wherein the amount of electromagnetic energy preferentially melts the material within the one or more first regions.

9. The method of claim 8, further comprising heating a substrate support so that the substrate positioned thereon is at a temperature between about 20°

C. and about 600°

C. before the electromagnetic energy is delivered to the surface of the substrate.

10. The method of claim 8, further comprising cooling a substrate support so that the substrate positioned thereon is at a temperature between about −

240°

C. and about 20°

C. before the electromagnetic energy is delivered to the surface of the substrate.

11. The method of claim 8, wherein modifying the first region includes disposing an alloying material within the material of the one or more first regions, wherein the alloying material is selected from a group consisting of germanium, arsenic, gallium, carbon, tin, and antimony.

12. The method of claim 8, wherein the area on the surface of the substrate is between about 4 mm² and about 1000 mm².

13. A method of thermally processing a semiconductor substrate, comprising:

providing a substrate formed from a substrate material;

forming a buried region made of a first material on a surface of the substrate, wherein the first material has a first thermal conductivity;

depositing a second layer made of a second material over the buried region, wherein the second material has a second thermal conductivity;

forming a semiconductor device on the surface of the substrate, wherein a portion of the formed semiconductor device contains a portion of the second layer; and

delivering an amount of electromagnetic energy to a surface of a substrate which is in thermal communication with the second layer, wherein the amount of electromagnetic energy is adapted to cause a portion of the second material in thermal communication with the buried region to reach its melting point.

14. The method of claim 13, wherein the thermal conductivity of the first material is smaller than the thermal conductivity of the second material.

15. The method of claim 13, wherein the second material is selected from a group consisting of silicon, germanium, gallium arsenide, gallium phosphide, and gallium nitride.

16. The method of claim 13, wherein the first material is selected from a group consisting of silicon dioxide, silicon nitride, silicon carbon nitride, graphite, germanium, gallium arsenide, gallium phosphide, and gallium nitride.

17. A method of thermally processing a substrate, comprising:

positioning a substrate on a substrate support, wherein the substrate has a plurality of features formed on a surface of the substrate that contain a first region and a second region;

depositing a coating over the first and second regions, wherein the material from which the coating is formed has a desired heat capacity;

removing a portion of the coating so that the thickness of the coating over the first region has a desired thickness, wherein the average heat capacity across the substrate surface after removing a portion of the coating is generally uniform; and

delivering an amount of electromagnetic energy to an area that contains the first region and the second region, wherein the amount of electromagnetic energy causes the material within the first region to melt.

18. The method of claim 17, further comprising heating a substrate support so that the substrate positioned thereon is at a temperature between about 20°

C. and about 600°

C. before the electromagnetic energy is delivered to the surface of the substrate.

19. The method of claim 17, further comprising cooling a substrate support so that the substrate positioned thereon is at a temperature between about −

240°

C. and about 20°

C. before the electromagnetic energy is delivered to the surface of the substrate.

20. The method of claim 17, wherein modifying the first region includes disposing an alloying material within the material of the one or more first regions, wherein the alloying material is selected from a group consisting of germanium, arsenic, gallium, carbon, tin, and antimony.

21. A method of thermally processing a substrate, comprising:

providing a substrate that has a first feature and a second feature formed on a surface of the substrate, wherein the second feature contains a first region and a second region;

positioning the substrate on a substrate support;

depositing a coating over the first and second features;

removing a portion of the coating so that the coating is disposed over the second region and a surface of the first feature is exposed; and

delivering an amount of electromagnetic energy to an area that contains the first feature and the second feature, wherein the amount of electromagnetic energy causes the material within the first region of the second feature to melt.

22. The method of claim 21, further comprising heating a substrate support so that the substrate positioned thereon is at a temperature between about 20°

C. and about 600°

C. before the electromagnetic energy is delivered to the surface of the substrate.

23. The method of claim 21, further comprising cooling a substrate support so that the substrate positioned thereon is at a temperature between about −

240°

C. and about 20°

C. before the electromagnetic energy is delivered to the surface of the substrate.

24. The method of claim 21, wherein modifying the first region includes disposing an alloying material within the material of the one or more first regions, wherein the alloying material is selected from a group consisting of germanium, arsenic, gallium, carbon, tin, and antimony.

25. The method of claim 21, wherein at least a portion of the coating contains fluorosilicate glass (FSG), amorphous carbon, silicon dioxide, silicon carbide, silicon carbon germanium alloys (SiCGe), titanium (Ti), titanium nitride (TiN), tantalum (Ta), cobalt (Co), ruthenium (Ru), or silicon carbon nitride (SiCN).

26. A method of thermally processing a substrate, comprising:

delivering a first amount of electromagnetic energy at one or more desired wavelengths to a rear surface of the substrate to cause a material in one or more regions generally adjacent to a front surface of the substrate to melt, wherein the rear surface and the front surface are on opposite sides of the substrate and the front surface of the substrate contains one or more semiconductor devices formed thereon.

27. The method of claim 26, wherein the one or more desired wavelengths are all greater than about 1 micrometer.

28. The method of claim 26, wherein the substrate is formed from a material that is selected from a group consisting of silicon, germanium, gallium arsenide, gallium phosphide, and gallium nitride.

29. The method of claim 26, wherein the material in the one or more regions further comprise a material selected from a group consisting of germanium, arsenic, gallium, carbon, tin, and antimony.

30. The method of claim 26, further comprising delivering a second amount of electromagnetic energy at a wavelength less than about 570 nm to a surface of the substrate.

31. A method of thermally processing a substrate, comprising:

delivering a first amount of electromagnetic energy to a first region on a surface of a substrate, wherein the first amount of electromagnetic energy causes the substrate material within the first region to melt and cause the crystalline substrate material to become amorphous;

implanting a second material within the amorphous first region; and

delivering a second amount of electromagnetic energy to the first region, wherein the second amount of electromagnetic energy causes the material within the first regions to melt.

32. The method of claim 31, further comprising heating a substrate support so that the substrate positioned thereon is at a temperature between about 20°

C. and about 600°

C. before the second electromagnetic energy is delivered to the surface of the substrate.

33. The method of claim 31, further comprising cooling a substrate support so that the substrate positioned thereon is at a temperature between about −

240°

C. and about 20°

C. before the second electromagnetic energy is delivered to the surface of the substrate.