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CN-122028710-A - Method for accurately measuring doping element distribution in semiconductor layer

CN122028710ACN 122028710 ACN122028710 ACN 122028710ACN-122028710-A

Abstract

The invention provides a method for accurately measuring the distribution of doped elements in a semiconductor layer, which comprises the steps of providing a substrate, forming a doped semiconductor silicon layer with the doped elements on the substrate, forming a barrier layer on the doped semiconductor silicon layer to prevent the surface of the doped semiconductor silicon layer from being oxidized to form a silicon oxide layer, wherein the temperature for forming the barrier layer is lower than the temperature for forming the doped semiconductor silicon layer, and placing a structure after forming the barrier layer in a detection machine to measure the concentration of the doped elements in the doped semiconductor silicon layer. The invention forms a blocking layer on the doped semiconductor silicon layer to block the surface of the doped semiconductor silicon layer from being oxidized by silicon to form a silicon oxide layer, thereby avoiding the phenomenon of 'sucking boron and discharging phosphorus' and accurately measuring the distribution of doping elements in the doped semiconductor silicon layer.

Inventors

  • ZHU KUN
  • ZOU ZHIXUE
  • LI DACHUAN

Assignees

  • 芯恩（青岛）集成电路有限公司

Dates

Publication Date
20260512
Application Date
20260212

Claims (10)

  1. 1. A method for accurately measuring the distribution of doping elements in a semiconductor layer, comprising the steps of: providing a substrate, and forming a doped semiconductor silicon layer with doping elements on the substrate, wherein the doping elements comprise at least one of boron and phosphorus; Forming a blocking layer on the doped semiconductor silicon layer, wherein the blocking layer is used for blocking the surface of the doped semiconductor silicon layer from being oxidized to form a silicon oxide layer, and the temperature for forming the blocking layer is lower than the temperature for forming the doped semiconductor silicon layer; And placing the structure after the barrier layer is formed in a detection machine, and measuring the concentration of the doping element in the doped semiconductor silicon layer.
  2. 2. The method for accurately measuring the distribution of doping elements in a semiconductor layer according to claim 1, wherein the barrier layer is a silicon nitride layer, and the thickness of the barrier layer ranges from 0.5 nm to 10nm.
  3. 3. The method of accurately measuring the dopant profile of a semiconductor layer according to claim 2, wherein the method of forming the barrier layer comprises placing the structure after forming the doped semiconductor silicon layer in a reaction chamber and annealing in an NH 3 atmosphere to form the barrier layer.
  4. 4. The method for accurately measuring the distribution of doping elements in a semiconductor layer according to claim 3, wherein in the annealing treatment, the gas flow rate of NH 3 is 0.5-15 slm, the annealing temperature is 300-750 ℃ and the annealing time is 10-360 s.
  5. 5. The method of accurately measuring the dopant profile of a semiconductor layer according to claim 2, wherein the method of forming the barrier layer comprises placing the structure after the formation of the doped semiconductor silicon layer in a furnace tube, and forming the barrier layer by a furnace tube growth method.
  6. 6. The method for accurately measuring the distribution of doping elements in a semiconductor layer according to claim 5, wherein the process temperature for forming the barrier layer is 500-750 ℃ and the process time is 0.5-2 h.
  7. 7. The method for accurately measuring the distribution of doped elements in a semiconductor layer according to claim 1, wherein the barrier layer is an undoped silicon layer, the thickness of the barrier layer is 1-10 nm, and the barrier layer is not completely oxidized in the process of oxidizing the barrier layer to form a surface silicon oxide layer.
  8. 8. The method for accurately measuring the distribution of a dopant element in a semiconductor layer according to claim 7, wherein said barrier layer is formed by epitaxial growth.
  9. 9. The method for accurately measuring the distribution of a doping element in a semiconductor layer according to claim 1, wherein the doped semiconductor silicon layer is formed by an epitaxial growth method.
  10. 10. The method of accurately measuring the dopant element profile in a semiconductor layer according to claim 1, wherein the step of forming the doped semiconductor silicon layer comprises: forming an undoped semiconductor silicon layer on the substrate by adopting an epitaxial growth method; And forming the doping element in the undoped semiconductor silicon layer by adopting an ion implantation method or a thermal diffusion method so as to form the doped semiconductor silicon layer.

Description

Method for accurately measuring doping element distribution in semiconductor layer Technical Field The invention belongs to the technical field of semiconductors, and relates to a method for accurately measuring the distribution of doping elements in a semiconductor layer. Background In the semiconductor process, in order to realize the performance of the device, the doping element is selectively implanted in the modes of epitaxial growth, ion implantation or thermal diffusion, and if the distribution and concentration measurement of the doping element are inaccurate in the process, the performance of the device and the development progress are seriously affected, which is time-consuming and labor-consuming. In the doped semiconductor silicon layer, the doped boron element is usually doped to form a P-type conduction type, or the doped phosphorus element is doped to form an N-type conduction type, if the surface of the doped semiconductor silicon layer is oxidized to form a silicon oxide layer, the phenomenon of boron absorption and phosphorus discharge exists, namely, when the silicon oxide layer is contacted with the doped semiconductor silicon layer containing boron, the solubility of boron in the silicon oxide layer is far higher than that of boron in silicon, boron can migrate from the doped semiconductor silicon layer to the silicon oxide layer, the boron concentration at the interface of the doped semiconductor silicon layer and the silicon oxide layer is reduced, and further, the measurement result is inaccurate when the distribution and the concentration of the doped element in the doped semiconductor silicon layer are measured, and when the silicon oxide layer is contacted with the doped semiconductor silicon layer containing phosphorus, the phosphorus concentration at the interface of the doped semiconductor silicon layer and the silicon oxide layer is stacked, so that the phosphorus concentration at the interface of the doped semiconductor silicon layer and the silicon oxide layer is abnormally increased, and the measurement result of the distribution and the concentration of the doped element in the doped semiconductor silicon layer is not particularly disturbed when the measurement result of the distribution and the concentration of the doped element in the doped semiconductor silicon layer is measured, and the measurement result of the high-doped semiconductor layer is more accurate. Therefore, how to provide a method for accurately measuring the distribution of the doping element in the semiconductor layer, so as to accurately measure the distribution and concentration of the doping element in the doped semiconductor silicon layer, is a technical problem to be solved by those skilled in the art. It should be noted that the foregoing description of the background art is only for the purpose of providing a clear and complete description of the technical solution of the present application and is presented for the convenience of understanding by those skilled in the art. The above-described solutions are not considered to be known to the person skilled in the art simply because they are set forth in the background of the application section. Disclosure of Invention In view of the above-mentioned drawbacks of the prior art, an object of the present invention is to provide a method for accurately measuring the distribution of doping elements in a semiconductor layer, which is used for solving the problem of inaccurate measurement of doping elements in a doped semiconductor silicon layer caused by the phenomenon of "boron absorption and phosphorus removal" in the prior art. To achieve the above and other related objects, the present invention provides a method for accurately measuring a doping element distribution in a semiconductor layer, comprising the steps of: providing a substrate, and forming a doped semiconductor silicon layer with doping elements on the substrate, wherein the doping elements comprise at least one of boron and phosphorus; Forming a blocking layer on the doped semiconductor silicon layer, wherein the blocking layer is used for blocking the surface of the doped semiconductor silicon layer from being oxidized to form a silicon oxide layer, and the temperature for forming the blocking layer is lower than the temperature for forming the doped semiconductor silicon layer; And placing the structure after the barrier layer is formed in a detection machine, and measuring the concentration of the doping element in the doped semiconductor silicon layer. Optionally, the barrier layer is a silicon nitride layer, and the thickness of the barrier layer ranges from 0.5 nm to 10nm. Optionally, the method for forming the barrier layer comprises the steps of placing the structure after the doped semiconductor silicon layer is formed in a reaction chamber, and annealing in an NH 3 atmosphere to form the barrier layer. Optionally, in the annealing treatment, the gas flow of NH 3 is 0.5-15 slm,