CN-121980887-A - Method and system for introducing high-energy particle source to optimize uniformity of two-dimensional argon plasma

CN121980887ACN 121980887 ACN121980887 ACN 121980887ACN-121980887-A

Abstract

The invention discloses a method and a system for introducing high-energy particle sources to optimize uniformity of two-dimensional argon plasma, which comprise the steps of S1, filling background gas into a plasma reaction chamber to simulate distribution of neutral particles, S2, initializing speed and position of charged particles in the chamber gas to uniformly distribute the charged particles in the chamber, determining intensity, time sequence, incidence direction and position of the high-energy particles emitted by external particle sources, S3, calculating density, electric potential and electric field of the charged particles, S4, calculating force acting on the charged particles, S5, moving the charged particles, S6, checking and executing collision, S7, repeating the steps S3-S6, adjusting the injection time sequence of the high-energy particles until reaching a steady state, and obtaining data distribution of the charged particles. The invention actively generates seed electrons-ions or changes energy distribution in a specific space region through controllable interaction between an external particle source and plasma or background gas, and compensates inherent spatial non-uniformity of the plasma.

Inventors

CHEN YONG
Cui Chengshuai
HU YONG

Assignees

安徽理工大学

Dates

Publication Date: 20260505
Application Date: 20251127

Claims (8)

1. A method for optimizing two-dimensional argon plasma uniformity by introducing a high-energy particle source, which is characterized by comprising the following steps: S1, filling background gas into a plasma reaction chamber, determining background gas parameters, dividing the chamber into grids, and simulating the distribution of neutral particles; s2, initializing the speed and the position of charged particles in the chamber gas, uniformly distributing the charged particles in the chamber, and determining the intensity, the time sequence, the incidence direction and the position of high-energy particles sent by an external particle source; s3, calculating the density of charged particles at each grid point of each time step so as to obtain space charge density distribution, and calculating the electric potential and electric field distribution on each grid node in the plasma; S4, interpolating the electric field value to the position of the particle through interpolation of a known electric field, and calculating the force of the electric field acting on the particle; S5, pushing the particles to move according to the force acting on the particles, judging whether the particles reach the boundary, and deleting the particles reaching the boundary; S6, judging whether all the particles with points collide with neutral particles, and if so, updating the number, speed and position of the particles according to the type of collision; and S7, repeating the step S3-the step S6, and adjusting the high-energy particle injection time sequence until the inside of the reaction chamber reaches a steady state, so as to obtain the data distribution of the charged particles.
2. The method of optimizing two-dimensional argon plasma uniformity by introducing a high energy particle source according to claim 1, wherein in step S2: The initial position and initial velocity of the energetic particles need to satisfy the following formula: left plate high energy particle incidence position: ; ; right plate high energy particle incidence position: ; ; Wherein, the The abscissa of the left plate incident particle is shown, Representing the ordinate of the left plate incident particles, The abscissa of the incident particles of the right plate is shown, Indicating the ordinate of the incident particles of the right plate, Is shown in the interval Random numbers uniformly distributed on the X-axis, X represents the length of the corresponding X-axis, Representing the corresponding y-axis length; Particle energy is : ; ; ; ; ; Wherein, the The mass of the particles is indicated and, Indicating the velocity of the particles, Representing the angle between the velocity vector and the positive x-axis, Representing the angle between the projection of the velocity vector onto the xy-plane and the positive x-axis.
3. The method of optimizing two-dimensional argon plasma uniformity by introducing a high energy particle source according to claim 1, wherein the charged particle density formula in step S3 is calculated as follows: The grid spacing is And The particles p are located at (xp, yp) and have a charge Qp for the nearest grid point coordinates Defining a normalized distance: ; Wherein, the 、 Respectively representing normalized distances of an x axis and a y axis; The weights W assigned to the four nodes are: ; ; ; ; traversing all particles, and accumulating the charge of each particle on the grid nodes according to the weight of each particle: ; ; ; ; Wherein, the Indicating the height of the electrode(s), Indicating the charge density, N indicating the number of charged particles present; according to charge density Solving for electric potential Then calculating an electric field E; ; ; ; ; Wherein, the Indicating the dielectric constant.
4. A method of optimizing two-dimensional argon plasma uniformity by introducing a high energy particle source according to claim 3, wherein in step S4 the force exerted by the electric field on the particles is calculated as: ; ; Wherein, the Indicating the force of the electric field acting on the particle p.
5. The method of optimizing two-dimensional argon plasma uniformity by introducing a high energy particle source according to claim 4, wherein the velocity and position of all particles are updated in step S5 based on the force exerted by the particles; ; Wherein, the Representing the mass of the particle p; the speed of the particles is updated in half integer time steps and the particle positions are updated in integer time steps; Update speed: ; ; Wherein t represents the number of the group consisting of, Representing a time step; updating the position: ; ; whether the charged particles reach the boundary is determined, and the charged particles reaching the boundary are subjected to a deletion process.
6. A method for optimizing two-dimensional argon plasma uniformity by introducing a high energy particle source according to claim 5, wherein the collisions in step S6 are divided into two major categories, the first major category being collisions of electrons with neutral particles and the second major category being collisions of ions with neutral particles, at a given time step each A decision regarding the occurrence of collisions must be made for each particle, and the probability of collisions for each particle is calculated as follows: ; Wherein, the Indicating the density of the background gas, Indicating the total collision cross section of the charged particles with the neutral particles, Indicating the relative velocity of the collision of charged particles with neutral particles, will And one in the interval Random numbers uniformly distributed on the surface Comparing if Less than A collision is considered to occur.
7. The method for optimizing two-dimensional argon plasma uniformity by introducing a high-energy particle source according to claim 1, wherein: in step S1, the background gas is argon.
8. A system for optimizing two-dimensional argon plasma uniformity by introducing a high-energy particle source, wherein the method for optimizing two-dimensional argon plasma uniformity by introducing a high-energy particle source according to any one of claims 1 to 7 is applied, and comprises the following steps: the plasma reaction cavity is used for introducing background gas and applying energy to excite the background gas to form plasma; the high-energy particle source emission module is used for introducing an external particle source into a plasma region or a nearby region of the plasma reaction cavity, the particle source emits particles with preset energy and intensity, and extra electron-ion pairs are generated or local electron energy distribution is changed in a target region by utilizing interaction between the particles and background gas or plasma in the reaction cavity, so that the spatial non-uniformity of the plasma is actively compensated, and the uniformity of the plasma density and energy distribution is realized.

Description

Method and system for introducing high-energy particle source to optimize uniformity of two-dimensional argon plasma Technical Field The invention relates to the technical field of plasma simulation, in particular to a method for optimizing two-dimensional argon plasma uniformity by introducing a high-energy particle source. Background The plasma is used as a fourth state of substances, consists of a large number of charged particles (including electrons and ions) and neutral particles, and is widely applied to the fields of microelectronic device manufacturing, material surface modification, film deposition, etching, plasma physical research and the like. In many practical applications, especially in semiconductor manufacturing where process accuracy is extremely high, the spatial uniformity of the plasma directly determines the uniformity of the processing effect, such as directly affecting the uniformity of the wafer surface film thickness, the verticality of the etch profile, and the uniformity of the doping profile, which are key factors affecting device performance and product yield. However, due to the restriction of various physical factors such as discharge characteristics, cavity structures, gas flow fields, boundary effects, and external electromagnetic field distribution, the spatial distribution of the plasma in the reaction cavity often presents an uneven state, such as density and energy difference between an edge area and a central area, so that the reaction rates at different positions on the surface of the substrate are inconsistent, and the overall quality of the process is affected. Disclosure of Invention The present invention aims to solve at least one of the technical problems in the related art to some extent. Therefore, an object of the present invention is to provide a method and a system for optimizing two-dimensional argon plasma uniformity by introducing high-energy particle source, wherein seed electrons-ions are actively generated or energy distribution is changed in a specific space region through controllable interaction between an external particle source and plasma or background gas, so as to compensate inherent spatial non-uniformity of the plasma and improve process uniformity. According to a first aspect, the invention provides a method for introducing a high-energy particle source to optimize the uniformity of two-dimensional argon plasma, which comprises the following steps: S1, filling background gas into a plasma reaction chamber, determining background gas parameters, dividing the chamber into grids, and simulating the distribution of neutral particles; s2, initializing the speed and the position of charged particles in the chamber gas, uniformly distributing the charged particles in the chamber, and determining the intensity, the time sequence, the incidence direction and the position of high-energy particles sent by an external particle source; s3, calculating the density of charged particles at each grid point of each time step so as to obtain space charge density distribution, and calculating the electric potential and electric field distribution on each grid node in the plasma; S4, interpolating the electric field value to the position of the particle through interpolation of a known electric field, and calculating the force of the electric field acting on the particle; S5, pushing the particles to move according to the force acting on the particles, judging whether the particles reach the boundary, and deleting the particles reaching the boundary; S6, judging whether all the particles with points collide with neutral particles, and if so, updating the number, speed and position of the particles according to the type of collision; and S7, repeating the step S3-the step S6, and adjusting the high-energy particle injection time sequence until the inside of the reaction chamber reaches a steady state, so as to obtain the data distribution of the charged particles. Preferably, in step S2: The initial position and initial velocity of the energetic particles need to satisfy the following formula: left plate high energy particle incidence position: right plate high energy particle incidence position: Wherein, the The abscissa of the left plate incident particle is shown,Representing the ordinate of the left plate incident particles,The abscissa of the incident particles of the right plate is shown,Indicating the ordinate of the incident particles of the right plate,Is shown in the intervalRandom numbers uniformly distributed on the X-axis, X represents the length of the corresponding X-axis,Representing the corresponding y-axis length; Particle energy is : Wherein, the The mass of the particles is indicated and,Indicating the velocity of the particles,Representing the angle between the velocity vector and the positive x-axis,Representing the angle between the projection of the velocity vector onto the xy-plane and the positive x-axis. Preferably, the charged particl