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CN-120020280-B - Electroplating method and electroplating device

CN120020280BCN 120020280 BCN120020280 BCN 120020280BCN-120020280-B

Abstract

The invention provides an electroplating method and an electroplating device, and relates to the technical field of semiconductor processing, wherein the electroplating method comprises the steps of S10, applying positive voltage to a middle anode, enabling an edge electrode to not work, S20, obtaining the deposition rate of a plating layer in the middle area to be v1, obtaining the deposition rate of the plating layer in the edge area to be v2, S30, judging the sizes of v1 and v2, S40, applying positive voltage to the edge electrode and outputting current I if v1 is greater than v2, S50, applying negative voltage to the edge electrode and outputting current I if v1 is less than v2, and S60, keeping the working state of the edge electrode unchanged if v1=v2. According to the invention, the deposition rates of the plating layers in the middle area and the edge area are respectively obtained, and the deposition rates of the edge area can be dynamically adjusted according to the control of the voltage and the current of the edge electrode, so that the deposition rates of the edge area and the middle area can be balanced in real time, and the electroplating uniformity is improved.

Inventors

  • Shi Die
  • REN ZHENGBO
  • Chen haotian
  • JIN YINUO
  • HU YULU
  • SUN KAIKAI

Assignees

  • 盛美半导体设备(上海)股份有限公司

Dates

Publication Date
20260512
Application Date
20231120

Claims (20)

  1. 1. An electroplating method, comprising providing an electroplating device comprising a central anode and an edge electrode, wherein the central anode corresponds to a central region of a substrate, the edge electrode is arranged around the periphery of the central anode and corresponds to an edge region of the substrate, and the electroplating method further comprises: s10, applying positive voltage to the middle anode, wherein the edge electrode does not work; S20, acquiring a deposition rate v1 of the coating in the middle area, and acquiring a deposition rate v2 of the coating in the edge area; s30, judging the sizes of v1 and v 2; S40, if v1 is larger than v2, applying positive voltage to the edge electrode and outputting current I; s50, if v1 is smaller than v2, applying negative voltage to the edge electrode and outputting current I; And S60, if v1=v2, keeping the working state of the edge electrode unchanged.
  2. 2. The electroplating method according to claim 1, wherein the step S40 further comprises: S41, v1 and v2 are obtained; s42, judging the sizes of v1 and v 2; s43, if v1 is smaller than v2, applying positive voltage to the edge electrode and reducing output current I; s45, if v1=v2, keeping the working state of the edge electrode unchanged; s46, if v1> v2, a positive voltage is applied to the edge electrode, and the output current I is increased, and then the process returns to step S41.
  3. 3. The plating method according to claim 2, characterized by further comprising, after step S43: S44, judging whether the output current I is 0, if I is not equal to 0, returning to the step S41, and if I is equal to 0, returning to the step S30.
  4. 4. The plating method according to claim 1, further comprising, after step S50: S51, v1 and v2 are obtained; S52, judging the sizes of v1 and v 2; s53, if v1 is smaller than v2, applying negative voltage to the edge electrode and increasing output current I; S54, if v1=v2, keeping the working state of the edge electrode unchanged; S55, if v1> v2, a negative voltage is applied to the edge electrode, and the output current I is reduced.
  5. 5. The plating method according to claim 4, further comprising, after step S55: S56, judging whether the output current I is 0, if I is not equal to 0, returning to the step S51, and if I is equal to 0, returning to the step S30.
  6. 6. The electroplating method according to claim 1, wherein step S20 specifically comprises: disposing a middle thickness detector on the electroless plating surface of the middle region; Calculating v1 by the thickness value output by the middle thickness detector and the detection frequency of the middle thickness detector; disposing an edge thickness detector on the electroless plating surface of the edge region; V2 is calculated from the thickness value output from the edge thickness detector and the detection frequency of the edge thickness detector.
  7. 7. The electroplating method according to claim 6, wherein the middle thickness detector comprises a plurality of middle eddy current sensors and a middle thickness calculating module, the method comprises the steps of obtaining the corresponding relation between the electric signals output by the middle eddy current sensors and the plating thickness through a standard sample wafer, and the middle thickness calculating module receives the electric signals output by the plurality of middle eddy current sensors and outputs a thickness value through an averaging method according to the corresponding relation; the edge thickness detector comprises a plurality of edge vortex sensors and an edge thickness calculating module, wherein the corresponding relation between the electrical signals output by the edge vortex sensors and the thickness of a coating is obtained through a standard sample wafer, and the edge thickness calculating module receives the electrical signals output by the plurality of edge vortex sensors and outputs a thickness value through an averaging method according to the corresponding relation.
  8. 8. An electroplating apparatus comprising an electroplating bath for containing an electroplating solution, the electroplating apparatus further comprising: A middle anode arranged in the electroplating solution and corresponding to the middle region of the substrate; A middle power supply connected to the clamping area of the substrate and the middle anode for applying a positive voltage to the middle anode and a negative voltage to the substrate; An edge electrode disposed around the outer periphery of the middle electrode and corresponding to an edge region of the substrate; An edge power supply connected to the clamping area of the substrate and the edge electrode; a middle rate detection module, configured to obtain a plating deposition rate v1 of a middle region of the substrate; the edge rate detection module is used for acquiring a plating layer deposition rate v2 of the edge area of the substrate; and the control module is used for comparing the magnitudes of v1 and v2 and controlling the positive and negative voltages and the magnitude of current applied by the edge power supply to the edge electrode according to the comparison result.
  9. 9. The electroplating apparatus of claim 8, wherein the mid-rate detection module comprises: the middle thickness detector is used for acquiring the thickness value of the plating layer; and the middle rate calculation module is used for calculating the deposition rate of the plating layer in the middle area according to the thickness value and the detection frequency of the middle thickness detector.
  10. 10. The electroplating apparatus of claim 9, wherein the mid-thickness detector comprises: The middle vortex sensors are distributed on the electroless plating surface of the middle area of the substrate at intervals; and the middle thickness calculation module is connected with the plurality of middle vortex sensors and is used for receiving the electric signals of the plurality of middle vortex sensors and outputting the average thickness value of the middle area.
  11. 11. The electroplating apparatus of claim 8, wherein the edge rate detection module comprises: the edge thickness detector is used for acquiring the thickness value of the plating layer; And the edge rate calculation module is used for calculating the deposition rate of the plating layer in the edge area according to the thickness value and the detection frequency of the edge thickness detector.
  12. 12. The electroplating apparatus of claim 11, wherein the edge thickness detector comprises: The edge vortex sensors are distributed on the non-electroplating surface of the edge area of the substrate at intervals; And the edge thickness calculation module is connected with the plurality of edge vortex sensors, and is used for receiving the electric signals of the plurality of edge vortex sensors and outputting the average thickness value of the edge area.
  13. 13. An electroplating method, comprising providing an electroplating device, the electroplating device comprising a central anode and an edge electrode, the central anode corresponding to a central region of a substrate, the edge electrode being disposed around the periphery of the central anode and corresponding to an edge region of the substrate, the electroplating method further comprising: s1000, applying a positive voltage to the middle anode, applying a positive voltage to the edge electrode, and outputting a current I; S1100, acquiring a deposition rate v1 of the coating in the middle area and acquiring a deposition rate v2 of the coating in the edge area; S1200, judging the sizes of v1 and v 2; s1300, if v1> v2, applying positive voltage to the edge electrode, increasing output current I, and returning to step S1100; s1400, if v1=v2, keeping the working state of the edge electrode unchanged; s1500, if v1< v2, applying positive voltage to the edge electrode and reducing output current I.
  14. 14. The plating method according to claim 13, further comprising, after step S1500: S1600, judging whether the applied current I is 0, if not, returning to the step S1100; if I is equal to 0, step S1700 is performed to apply a negative voltage to the edge electrode and output a current I.
  15. 15. The plating method of claim 14, further comprising, after step S1700: s1710, v1 and v2 are obtained; s1720, judging the sizes of v1 and v 2; s1730, if v1< v2, applying a negative voltage to the edge electrode and increasing the output current I, then returning to step S1710; S1740, if v1=v2, keeping the working state of the edge electrode unchanged; S1750, if v1> v2, applying a negative voltage to the edge electrode, and reducing the output current I.
  16. 16. The plating method according to claim 15, further comprising, after step S1750: S1760, judging whether the output current I is 0, if not, returning to step S1710; If I is equal to 0, go back to step S1000.
  17. 17. An electroplating method, comprising providing an electroplating device comprising a central anode and an edge electrode, wherein the central anode corresponds to a central region of a substrate, the edge electrode is arranged around the periphery of the central anode and corresponds to an edge region of the substrate, and the electroplating method further comprises: S2000, applying a positive voltage to the middle anode, applying a negative voltage to the edge electrode, and outputting a current I; s2100, acquiring a deposition rate v1 of the coating of the middle area and a deposition rate v2 of the coating of the edge area; s2200, judging the sizes of v1 and v 2; s2300, if v1< v2, applying a negative voltage to the edge electrode and increasing the output current I, and returning to step S2100; s2400, if v1=v2, keeping the working state of the edge electrode unchanged; s2500, if v1> v2, applying a negative voltage to the edge electrode, and reducing the output current I.
  18. 18. The plating method of claim 17, further comprising, after step S2500: S2600, judging whether the output current I is 0, if I is not 0, returning to the step S2100, if I is 0, executing the step S2700, applying positive voltage to the middle anode, applying positive voltage to the edge electrode, and outputting the current I.
  19. 19. The plating method of claim 18, further comprising, after step 2700: S2710, v1 and v2 are obtained; S2720, judging the sizes of v1 and v 2; S2730, if v1> v2, applying positive voltage to the edge electrode, increasing output current I, and returning to step S2710; s2740, if v1=v2, keeping the working state of the edge electrode unchanged; S2750, if v1< v2, applying a positive voltage to the edge electrode and reducing the output current I.
  20. 20. The electroplating method of claim 19, further comprising, after step 2750: S2760, determining whether the output current I is 0, if i=0, returning to step S2000; if I is not equal to 0, go back to step S2710.

Description

Electroplating method and electroplating device Technical Field The invention relates to the technical field of semiconductor processing, in particular to an electroplating method and an electroplating device. Background In the electroplating field, the seed layer is a thin metal layer formed on the surface of a substrate by chemical or physical methods. The seed layer is an essential step in the electroplating process and serves to guide and promote the deposition of the metal. In order to increase the area of the effective plating area, the conventional plating apparatus has no direct contact with the seed layer on the substrate at the edge region of the substrate and at the center region of the substrate. The higher the resistivity of the seed layer material, the thinner the thickness, the greater the resistance and the greater the current density distribution difference. Since the electrical contact locations are at the edge regions of the substrate, the current density at the edge regions of the substrate is much higher than the current density at the middle regions of the substrate. This uneven distribution of current density can lead to a severe non-uniformity of the thickness of the edge plating layer and the center of the substrate. In this case, the current solution is to use an electroplating device with multiple anodes, wherein each anode is independently controlled, and the power of each anode in the electroplating process is controlled through a preset program according to the coating thickness difference obtained through experiments in advance. However, this solution is poorly suited, and only for a specific seed layer, the procedure needs to be reset after the seed layer replacement. Disclosure of Invention In order to solve the above problems in the prior art, the present invention provides an electroplating method and an electroplating apparatus. The invention solves the technical problems by the following technical proposal: an electroplating method comprising providing an electroplating apparatus comprising a central anode corresponding to a central region of a substrate and an edge electrode corresponding to an edge region of the substrate, the electroplating method further comprising: s10, applying positive voltage to the middle anode, wherein the edge electrode does not work; S20, acquiring a deposition rate v1 of the coating in the middle area, and acquiring a deposition rate v2 of the coating in the edge area; s30, judging the sizes of v1 and v 2; S40, if v1 is larger than v2, applying positive voltage to the edge electrode and outputting current I; s50, if v1 is smaller than v2, applying negative voltage to the edge electrode and outputting current I; And S60, if v1=v2, keeping the working state of the edge electrode unchanged. According to the method, positive voltage is firstly applied to the middle anode, the edge electrode does not work, the difference of the deposition rates of the edge region and the middle region can be obtained by respectively obtaining the deposition rates of the plating layers of the middle region and the edge region, and the voltage and the output current of the edge electrode are controlled according to the difference, so that the thicknesses of the plating layers of the middle region and the edge region of the substrate are more approximate, and the electroplating uniformity is improved. The invention also provides an electroplating device, which comprises an electroplating bath, wherein the electroplating bath is used for containing electroplating liquid, and the electroplating device further comprises: A middle anode arranged in the electroplating solution and corresponding to the middle region of the substrate; A middle power supply connected to the edge region of the substrate and the middle anode for applying a positive voltage to the middle anode and a negative voltage to the substrate; An edge electrode disposed around the outer periphery of the middle electrode and corresponding to an edge region of the substrate; An edge power supply connected to the clamping area of the substrate and the edge electrode; a middle rate detection module, configured to obtain a plating deposition rate v1 of a middle region of the substrate; the edge rate detection module is used for acquiring a plating layer deposition rate v2 of the edge area of the substrate; the control module is used for comparing the magnitude of v1 and v2 and controlling the magnitude of positive and negative voltage and current applied by the edge power supply to the edge electrode according to the comparison result. The electroplating device is provided with a middle power supply and an edge power supply, the middle power supply can independently supply power to the middle anode, the edge power supply can independently supply power to the edge electrode, and the control of the middle anode and the control of the edge electrode are relatively independent. Through setting up middle part rat