CN-122013314-A - Polysilicon deposition nozzle regulation and control system based on fluid field control

CN122013314ACN 122013314 ACN122013314 ACN 122013314ACN-122013314-A

Abstract

The invention relates to the technical field of polysilicon deposition, in particular to a polysilicon deposition nozzle regulation and control system based on fluid field control, which comprises a fluid field monitoring module, a fluid analysis module and a nozzle regulation and control module, wherein the fluid field monitoring module is used for collecting fluid field distribution data and nozzle parameters of all positions in a polysilicon deposition cavity in real time, the fluid analysis module is used for determining vortex distribution conditions and/or dead zone distribution conditions in the fluid field based on fluid field distribution data change conditions of all positions in the polysilicon deposition cavity in a preset time period and determining defect change types, and the nozzle regulation module is used for determining a plurality of associated nozzles based on the vortex distribution conditions and/or dead zone distribution conditions in the fluid field and determining nozzle regulation modes based on the defect change types and the number of the associated nozzles. The invention can improve the regulation and control accuracy of the nozzle and ensure the deposition uniformity of the polysilicon.

Inventors

WANG FUGANG
TIAN XIN
WU FENG
WANG ZHEN

Assignees

江苏鑫华半导体科技股份有限公司

Dates

Publication Date: 20260512
Application Date: 20260413

Claims (10)

1.A fluid field control-based polysilicon deposition nozzle conditioning system, comprising: The fluid field monitoring module is used for collecting fluid field distribution data and nozzle parameters of all positions in the polysilicon deposition cavity in real time, wherein the fluid field distribution data comprise flow field flow velocity, fluid pressure and fluid concentration, and the nozzle parameters comprise nozzle length, injection angle and nozzle working state; The fluid analysis module is used for determining vortex distribution conditions and/or dead zone distribution conditions in the fluid field based on the fluid field distribution data change conditions of each position in the polysilicon deposition cavity in a preset time period and determining defect change types, wherein the defect change types comprise a stable frequent occurrence type and an unstable frequent occurrence type; A nozzle adjustment module to determine a number of associated nozzles based on a vortex distribution and/or a dead zone distribution within the fluid field and to determine a nozzle adjustment based on the defect variation type and the number of associated nozzles, including, Determining a nozzle length adjustment amount based on a vortex distribution condition and/or a dead zone distribution condition within the fluid field under a first relative condition to adjust a nozzle length of the associated nozzle; under a second relative condition, determining an abnormal distribution area based on the vortex distribution condition and/or the dead zone distribution condition so as to adjust the working state of the nozzle in the abnormal distribution area; and under a third relative condition, determining a nozzle adjustment coefficient based on the distribution condition of each associated nozzle so as to adjust the injection angle of the nozzles in the polysilicon deposition cavity.
2. The polysilicon deposition nozzle regulation and control system based on fluid field control according to claim 1, wherein the fluid analysis module divides the preset time period into a plurality of monitoring periods, determines a plurality of abnormal circulation areas based on flow field flow velocity change conditions of each position in the polysilicon deposition cavity in the preset time period, and determines a local change characterization value corresponding to the abnormal circulation area in the monitoring period based on flow field pressure and flow field concentration of any abnormal circulation area in any monitoring period so as to determine whether vortex exists in the abnormal circulation area in the monitoring period.
3. The polysilicon deposition nozzle regulation and control system based on fluid field control of claim 2, wherein the fluid analysis module determines a plurality of candidate dead zone areas based on the fluid concentration change conditions of each position in the polysilicon deposition chamber within the preset time period, and determines whether a dead zone exists in the candidate dead zone areas within the monitoring period based on the concentration change characterization value and the pressure change characterization value of any one of the candidate dead zone areas within any one of the monitoring periods; The concentration change characterization value is determined based on a comparison result of the concentration of the flow field of the candidate dead zone region and a preset concentration in the monitoring period; And the pressure change characterization value is determined based on a comparison result of the flow field pressure change rate of the candidate dead zone region and a preset pressure change rate in the monitoring period.
4. The polysilicon deposition nozzle regulation and control system based on fluid field control of claim 3 wherein the fluid analysis module determines whether a vortex exists in the abnormal circulation region in any of the monitoring periods based on a comparison of a local variation characterization value corresponding to any of the abnormal circulation regions in any of the monitoring periods with a first preset variation threshold.
5. The fluid field control-based polysilicon deposition nozzle regulation system of claim 4 wherein the fluid analysis module determines whether a dead zone exists in the candidate dead zone region in the monitoring period based on a comparison of a concentration variation characterization value of any of the candidate dead zone regions to a second preset variation threshold and a comparison of a pressure variation characterization value to a third preset variation threshold in any of the monitoring periods.
6. The polysilicon deposition nozzle regulation system based on fluid field control of claim 5, wherein the fluid analysis module determines a defect variation type based on a comparison of the number of anomaly monitoring periods to a preset number; wherein the abnormality monitoring period is a monitoring period in which eddy currents and/or dead zones exist.
7. The fluid field control-based polysilicon deposition nozzle regulation system of claim 6 wherein the nozzle adjustment module determines a number of the associated nozzles based on a comparison of critical eddy current regions to each nozzle irradiation region and a comparison of critical dead zone regions to each nozzle irradiation region; The critical eddy current area is an abnormal circulation area set with eddy current in any monitoring period; the key dead zone is a candidate dead zone set with dead zones in any monitoring period; any of the nozzle irradiation regions is determined based on nozzle parameters of any of the nozzles.
8. The fluid field control-based polysilicon deposition nozzle regulation system of claim 7 wherein the nozzle adjustment module determines a region emissivity based on a comparison of the critical vortex region and an associated nozzle emissivity region and/or a comparison of the critical dead zone region and an associated nozzle emissivity region under a first relative condition, and determines a nozzle length adjustment based on the region emissivity and a preset nozzle length; Wherein the first relative condition is that the defect change type is stable and frequently occurs and the number of associated nozzles is unique.
9. The polysilicon deposition nozzle regulation system based on fluid field control of claim 8, wherein the nozzle adjustment module determines an abnormal distribution region based on the critical eddy current region and/or the critical dead zone region and adjusts the operating states of the nozzles in the abnormal distribution region to all start-up states under a second relative condition; wherein the working state comprises a starting state and a stopping state; the second relative condition is that the defect change type is that instability frequently occurs and the associated number of nozzles is unique.
10. The polysilicon deposition nozzle regulation system based on fluid field control of claim 9, wherein the nozzle adjustment module clusters each of the associated nozzles under a third relative condition to determine a number of cluster groups, and determines a nozzle adjustment coefficient corresponding to each cluster group based on the number of associated nozzles in each cluster group to adjust a nozzle injection angle in a critical vortex region and/or a critical dead region corresponding to each cluster group; Wherein the third relative condition is that the number of associated nozzles is not unique.

Description

Polysilicon deposition nozzle regulation and control system based on fluid field control Technical Field The invention relates to the technical field of polysilicon deposition, in particular to a polysilicon deposition nozzle regulating and controlling system based on fluid field control. Background In the polysilicon chemical vapor deposition process, a reaction gas source is injected into the fluid field uniformity formed by the cavity through the deposition nozzle, and the quality of the deposition layer and the production yield are directly determined. The method is influenced by nozzle layout, air source fluctuation and cavity flow channel constraint, and the cavity fluid field is easy to generate two defects of vortex and dead zone, namely, turbulent mixing of gas is caused by vortex, abnormal local deposition rate is caused, byproducts are mixed, and reaction gas is retained due to the dead zone, so that cavity pollution and raw material loss are caused. The existing nozzle regulation and control is based on manual experience adjustment, quantitative identification means for vortex flow, dead zone quantity and distribution are lacked, mapping logic of defect characteristics, associated nozzle types and regulation and control modes is not established, homogenization regulation and control are adopted for defects caused by single/multiple nozzles and frequently occurring defects of stability/instability, pertinence is poor, defect eliminating effect is poor, and long-term stability of a polysilicon deposition fluid field is difficult to guarantee. Chinese laid-open patent CN107488836B discloses a method for depositing a polysilicon film, wherein a vertical tube furnace is used for depositing a polysilicon film by using silane as a reaction gas, and during deposition, the gas flow rates of the bottommost nozzle and the topmost nozzle are substantially the same and are greater than the gas flow rate of the middle nozzle, and the gas flow rate of the middle nozzle is sequentially increased from bottom to top. The reaction gas flows from bottom to top and is gradually consumed in the flowing process, the gas flow of the middle nozzle is sequentially increased, the consumed gas in the flowing process is compensated, the uniformity among wafers is improved, in addition, the gas flow at the top end is increased, the partial pressure caused by hydrogen generated by the reaction is reduced, and the uniformity of the polycrystalline silicon film in the top wafer is further improved. The prior art has the following problems that the fixed nozzle design is adopted, the state of the fluid field is adjusted only by changing the gas flow of the nozzle, and the lack of analysis and identification of eddy current and dead zone defects can cause the disturbance of the fluid field to be aggravated, so that the local deposition of polysilicon is uneven. Disclosure of Invention Therefore, the invention provides a polysilicon deposition nozzle regulation and control system based on fluid field control, which is used for solving the problems that the fluid field disturbance is aggravated and the local deposition of polysilicon is uneven due to the lack of analysis and identification of eddy current and dead zone defects caused by adopting a fixed nozzle design and adjusting the fluid field state by changing the nozzle gas flow in the prior art. To achieve the above object, the present invention provides a polysilicon deposition nozzle regulation system based on fluid field control, comprising: The fluid field monitoring module is used for collecting fluid field distribution data and nozzle parameters of all positions in the polysilicon deposition cavity in real time, wherein the fluid field distribution data comprise flow field flow velocity, fluid pressure and fluid concentration, and the nozzle parameters comprise nozzle length, injection angle and nozzle working state; The fluid analysis module is used for determining vortex distribution conditions and/or dead zone distribution conditions in the fluid field based on the fluid field distribution data change conditions of each position in the polysilicon deposition cavity in a preset time period and determining defect change types, wherein the defect change types comprise a stable frequent occurrence type and an unstable frequent occurrence type; A nozzle adjustment module to determine a number of associated nozzles based on a vortex distribution and/or a dead zone distribution within the fluid field and to determine a nozzle adjustment based on the defect variation type and the number of associated nozzles, including, Determining a nozzle length adjustment amount based on a vortex distribution condition and/or a dead zone distribution condition within the fluid field under a first relative condition to adjust a nozzle length of the associated nozzle; under a second relative condition, determining an abnormal distribution area based on the vortex distribution condition and/