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KR-102961619-B1 - Dopant diffusion through short high-temperature annealing pulses

KR102961619B1KR 102961619 B1KR102961619 B1KR 102961619B1KR-102961619-B1

Abstract

A method and apparatus for diffusing a dopant into a semiconductor device are described. The method includes the step of performing dynamic surface annealing in which a substrate is placed within a process volume having a mixture of an inert gas and a small amount of oxygen gas. Subsequently, the surface of the substrate is exposed to one or more rapid laser pulses. The rapid laser bursts diffuse the dopant from the doped layer into the substrate. The doped layer is formed during the preceding process operation. The temperature and the number of laser pulses control the amount of dopant diffusion into the substrate. Other dynamic surface annealing operations may optionally be performed before or after the oxygen-doped dynamic surface annealing operation.

Inventors

  • 아더홀트, 볼프강 알.

Assignees

  • 어플라이드 머티어리얼스, 인코포레이티드

Dates

Publication Date
20260508
Application Date
20230531
Priority Date
20220616

Claims (20)

  1. As a method for diffusing a dopant suitable for use during semiconductor processing, A step of flowing an inert gas into the process volume of a process chamber; A step of flowing the oxygen-containing gas into the process volume such that the oxygen partial pressure of the oxygen-containing gas is 0.1% to 10% within the process volume; and A step of exposing a portion of a substrate within the above process volume to one or more laser pulses to heat the portion of the substrate to a temperature higher than 850°C and diffusing the dopant into the substrate. A method including
  2. A method according to claim 1, wherein each of the one or more laser pulses has a duration of less than 1 second.
  3. In paragraph 2, the method wherein each of the laser pulses of the one or more laser pulses has a wavelength of 200 nm to 20000 nm.
  4. A method according to paragraph 3, wherein each of the laser pulses of the one or more laser pulses has a power density of 0.1 W/cm² to 10 W/cm².
  5. A method according to claim 1, wherein the inert gas is one of argon, nitrogen, helium, neon, krypton, and xenon or a combination thereof.
  6. A method according to claim 1, wherein 1 to 50 individual laser pulses exist within one or more laser pulses.
  7. A method according to claim 1, wherein the temperature of the portion of the substrate during exposure is 850°C to 1410°C.
  8. delete
  9. A method according to claim 1, wherein the upper surface of the substrate has a layer having a dopant concentration greater than 1·10 20 atoms/cm³ while the portion of the substrate is exposed to the one or more laser pulses.
  10. In claim 9, the method wherein the dopant is one or a combination of phosphorus, boron, arsenic, gallium, indium, aluminum, and lithium.
  11. As a method for diffusing a dopant suitable for use during semiconductor processing, A step of depositing a doped layer having a dopant—said that the doped layer has a dopant concentration greater than 1· 10²⁰ atoms/cm³ on the upper surface of a substrate in a first process chamber—; and Step of performing oxygen addition dynamic surface annealing The step of performing the oxygen-added dynamic surface annealing, comprising: A step of flowing an inert gas into the process volume of a second process chamber; A step of flowing the oxygen gas into the process volume such that the oxygen partial pressure of the oxygen gas is 0.1% to 10% within the process volume of the second process chamber; and Step of exposing a portion of a substrate within the above-mentioned process volume to one or more laser pulses to heat the portion of the substrate to a temperature higher than 800°C A method including
  12. In claim 11, the step of performing a first dynamic surface annealing in the second process chamber before performing the oxygen-added dynamic surface annealing is further included, and the first dynamic surface annealing is: A step of flowing an inert gas into the process volume of the second process chamber so that the inert gas partial pressure of the inert gas is greater than 99.9% within the process volume; and Step of exposing a portion of the substrate within the above process volume to a plurality of first laser pulses A method including
  13. In claim 11, the method wherein the doped layer has a concentration greater than 1· 10²¹ atoms/cm³ and a thickness of 0.1 nm to 2 nm.
  14. A method according to claim 11, wherein each of the one or more laser pulses has a duration of less than 0.1 seconds.
  15. In paragraph 11, the method wherein the inert gas is one or a combination of argon gas, nitrogen gas, helium, neon, krypton and xenon.
  16. A method according to claim 11, wherein 1 to 15 individual laser pulses exist within one or more laser pulses.
  17. In paragraph 11, the method wherein the dopant is one or a combination of phosphorus, boron, arsenic, gallium, indium, aluminum, and lithium.
  18. As a method for diffusing a dopant suitable for use during semiconductor processing, A step of selectively depositing a doped layer having a dopant on the upper surface of a substrate within a first process chamber—said that the doped layer has a dopant concentration greater than 1· 10²¹ atoms/cm³—; and A step of diffusing the dopant into the substrate by performing oxygen addition dynamic surface annealing - the step of diffusing the dopant into the substrate by performing oxygen addition dynamic surface annealing is: A step of flowing an inert gas into the process volume of a second process chamber; A step of flowing the oxygen gas into the process volume such that the oxygen partial pressure of the oxygen gas is 0.1% to 10% within the process volume of the second process chamber; and A step of exposing a portion of a substrate within the above process volume to a plurality of laser pulses to heat the portion of the substrate to a temperature higher than 800°C and diffusing the dopant into the substrate. Includes -; and Step of removing oxide formed on the substrate after diffusing the above dopant A method including
  19. A method according to claim 18, wherein after diffusing the dopant, the substrate has a second dopant concentration greater than 1· 10¹² atoms/cm³ at a depth of 20 nm from the upper surface.
  20. In claim 18, the method wherein the temperature of the portion of the substrate during exposure to the plurality of laser pulses is less than 1200°C.

Description

Dopant diffusion through short high-temperature annealing pulses The embodiments of the present disclosure generally relate to a method for forming a device. More specifically, the embodiments of the present disclosure relate to a method for doping a substrate that is part of a semiconductor device. Microelectronic devices are fabricated on semiconductor substrates as integrated circuits in which various conductive layers are interconnected to allow electronic signals to propagate within the device. An example of such a device is a complementary metal-oxide-semiconductor (CMOS) field-effect transistor (FET) or MOSFET. FETs can utilize fin or gate-all-around structures. More complex structures, such as fin and gate-all-around structures, require doping approaches that are used out of the line of sight of the dopant or heat source. Current doping methods suffer from poor dopant uniformity, poor repeatability of dopant profiles, defects within the dopant profiles, undesirable shape modifications of the dopant profiles, and dopant diffusion into the device structure that is larger than desired. In some dopant diffusion operations, such as bake annealing or rapid thermal processing (RTP) annealing, dopants diffuse through desired regions within the device and limit the minimum size of the semiconductor device. Some methods for diffusing dopants utilize temperatures that melt or deform the semiconductor device. In some operations, repetitive heating has been found to deform the semiconductor device. Therefore, in order to enable controlled diffusion of dopants into semiconductor devices, devices and methods having reduced temperatures and cycling are required. The present disclosure generally relates to the formation of a doped region within a semiconductor device structure. In one embodiment, a method for diffusing a dopant suitable for use during semiconductor processing is described. The method comprises the steps of flowing an inert gas into a process volume of a process chamber, flowing an oxygen gas into a process volume such that the oxygen partial pressure of the oxygen gas is about 0.1% to about 10% within the process volume, and exposing a portion of a substrate within the process volume to one or more laser pulses to heat a portion of the substrate to a temperature higher than about 850°C. In another embodiment, a method for diffusing a dopant into a semiconductor device structure comprises the steps of: depositing a doped layer having a dopant—the doped layer having a dopant concentration greater than about 1.10²⁰ atoms/cm³ on the upper surface of a substrate in a first process chamber—and performing oxygenated dynamic surface annealing. The oxygenated dynamic surface annealing comprises the steps of flowing an inert gas into a process volume of a second process chamber, flowing the oxygen gas into a process volume such that the oxygen partial pressure of the oxygen gas is about 0.1% to about 10% in the process volume of the second process chamber, and exposing a portion of the substrate in the process volume to one or more laser pulses to heat a portion of the substrate to a temperature higher than about 800°C. In another embodiment, a method for diffusing a dopant into a semiconductor device structure comprises the step of selectively depositing a doped layer having a dopant on the upper surface of a substrate in a first process chamber. The doped layer has a dopant concentration greater than about 1.10²¹ atoms/cm³. The method further comprises the step of diffusing the dopant into the substrate by performing oxygen-added dynamic surface annealing. Oxygen-added dynamic surface annealing comprises the steps of flowing an inert gas into the process volume of a second process chamber; flowing the oxygen gas into the process volume such that the oxygen partial pressure of the oxygen gas is about 0.1% to about 10% in the process volume of the second process chamber; exposing a portion of the substrate in the process volume to a plurality of laser pulses to heat a portion of the substrate to a temperature higher than about 800°C and diffusing the dopant into the substrate; and removing an oxide formed on the substrate after diffusing the dopant. In order to enable a detailed understanding of the features of the present disclosure described above, a more specific description of the present disclosure, which has been briefly summarized above, may be provided by reference to the embodiments, some of which are illustrated in the accompanying drawings. However, it should be noted that the accompanying drawings merely illustrate exemplary embodiments and are therefore not to be construed as limiting the scope thereof, and allow for other equally effective embodiments. FIG. 1 is a schematic plan view of an example of a semiconductor processing system according to one or more embodiments of the present disclosure. FIG. 2 is a schematic cross-sectional view of one type of sedimentation chamber according to one emb