Electrochemical deposition system incorporating an optical probe

Abstract

An electrochemical deposition system includes: an electrochemical deposition chamber including an electrolyte for electrochemical deposition; a substrate holder configured to hold a substrate and including a first cathode electrically connected to the substrate; a first actuator configured to adjust a vertical position of the substrate holder in the electrochemical deposition chamber; an anode immersed in the electrolyte; a second cathode configured to be between the first cathode and the anode; a first optical probe configured to measure a first reflectivity of the substrate at a first distance from a center of the substrate when the substrate is immersed in the electrolyte; and a controller configured to selectively adjust at least one of a power applied to the first cathode, a power applied to the second cathode, a power applied to the anode, and the vertical position of the substrate holder during the electrochemical deposition based on the first reflectivity of the substrate.

Description

[0001] Cross - reference to related applications

[0002] This application claims the benefit of U.S. Provisional Application No. 62 / 852,497, filed on May 24, 2019. The entire disclosure of the above - cited application is incorporated herein by reference. Technical field

[0003] The present disclosure relates to an electrochemical plating system, and more particularly to an electrochemical plating system including an optical probe. Background art

[0004] The background description provided here is for the purpose of generally presenting the background of the present disclosure. The work of the currently named inventors, to the extent it is described in this background art section and in various aspects of the specification that could not be determined to be prior art at the time of filing the application, is neither expressly nor implicitly admitted to be prior art against the present disclosure.

[0005] Electrochemical deposition can be used to fill features in a substrate from the bottom of the feature (e.g., trenches and / or vias) to the top of the feature (i.e., from bottom to top) with a material. Excess material deposited on top of the feature can be removed, for example, by a chemical mechanical planarization (CMP) process. In some examples, the material can be a metal such as copper, cobalt, tungsten, tin, silver, gold, ruthenium, titanium, tantalum, and oxides, nitrides, and alloys of these metals.

[0006] Controlling the uniformity of the deposition can help provide a uniform film for CMP and minimize voids in the features. If the material does not have a uniform thickness, under - polishing or over - polishing may occur during CMP. For example, over - polishing may occur in thin regions, while under - polishing may occur in thick regions. Over - polishing or under - polishing may increase voids and / or other defects. An increase in voids and / or other defects may additionally or alternatively occur if there is a difference between the first feature fill rate near the edge of the substrate and the second feature fill rate near the center of the substrate. Defects in an integrated circuit can cause electrical failures of the integrated circuit. Summary of the invention

[0007] In one aspect, an electrochemical deposition system includes: an electrochemical deposition chamber that includes an electrolyte for electrochemical deposition; a substrate holder configured to hold a substrate and including a first cathode electrically connected to the substrate; a first actuator configured to adjust a vertical position of the substrate holder within the electrochemical deposition chamber; an anode immersed in the electrolyte; a second cathode configured to be between the first cathode and the anode; a first optical probe configured to measure a first reflectivity of the substrate at a first distance from a center of the substrate while the substrate is immersed in the electrolyte during the electrochemical deposition; and a controller configured to selectively adjust at least one of (i) power applied to the first cathode, (ii) power applied to the second cathode, (iii) power applied to the anode, and (iv) the vertical position of the substrate holder based on the first reflectivity of the substrate during the electrochemical deposition.

[0008] In one aspect, a second optical probe is configured to measure a second reflectivity of the substrate at a second distance from the center of the substrate while the substrate is immersed in the electrolyte during the electrochemical deposition. The controller is configured to further selectively adjust at least one of (i) the power applied to the first cathode, (ii) the power applied to the second cathode, (iii) the power applied to the anode, and (iv) the vertical position of the substrate holder based on the second reflectivity of the substrate during the electrochemical deposition.

[0009] In one aspect, the first distance is different from the second distance.

[0010] In one aspect, the controller is configured to selectively adjust at least one of (i) the power applied to the first cathode, (ii) the power applied to the second cathode, (iii) the power applied to the anode, and (iv) the vertical position of the substrate holder based on a difference between the first reflectivity and the second reflectivity during the electrochemical deposition.

[0011] In one aspect, the controller is configured to, during the electrochemical deposition: determine a first adjustment based on the difference; and apply power to the first cathode based on the first adjustment and a value selected from a first distribution.

[0012] In one aspect, the controller is configured to, during the electrochemical deposition: determine a second adjustment based on the difference; and apply power to the second cathode based on the second adjustment and a value selected from a second distribution.

[0013] In one feature, during the electrochemical deposition, the controller is configured to: determine a third adjustment based on the difference; and adjust the vertical position of the substrate holder based on the third adjustment and a value selected from a third distribution.

[0014] In one feature, the first optical probe includes: a first light source configured to emit light perpendicular to the surface of the substrate during the electrochemical deposition when the substrate is immersed in the electrolyte; and a first light detector configured to receive light perpendicular to the surface of the substrate during the electrochemical deposition when the substrate is immersed in the electrolyte.

[0015] In one feature, the first optical probe includes: a first light source configured to emit light at an angle other than 90 degrees relative to the surface of the substrate during the electrochemical deposition when the substrate is immersed in the electrolyte; and a first light detector configured to receive light at an angle other than 90 degrees relative to the surface during the electrochemical deposition when the substrate is immersed in the electrolyte.

[0016] In one feature, a window is located between the first optical probe and the substrate. The first optical probe is configured to emit and receive light passing through the window during the electrochemical deposition when the substrate is immersed in the electrolyte.

[0017] In one feature, the first optical probe includes: a first light source configured to emit light perpendicular to the surface of the substrate during the electrochemical deposition when the substrate is immersed in the electrolyte; and a first light detector configured to receive light passing through the substrate during the electrochemical deposition when the substrate is immersed in the electrolyte.

[0018] In one feature, the first optical probe is located on a horizontally extending bar.

[0019] In one feature, the first optical probe is mounted to the wall of the electrochemical deposition chamber.

[0020] In one feature, the first optical probe is configured to emit and receive light of only a single wavelength.

[0021] In one feature, the first optical probe is configured to emit and receive light within a certain wavelength range.

[0022] In one feature, a second actuator is configured to rotate the substrate holder during the electrochemical deposition.

[0023] In one aspect, the controller is further configured to, during the electrochemical deposition: detect an end point of the electrochemical deposition based on the first reflectivity of the substrate; and in response to the detection of the end point, selectively adjust at least one of (i) the power applied to the first cathode, (ii) the power applied to the second cathode, (iii) the power applied to the anode, and (iv) the vertical position of the substrate holder.

[0024] In one aspect, the controller is further configured to, during the electrochemical deposition: determine the depth of a feature formed in the substrate based on the first reflectivity of the substrate; and based on the depth of the feature formed in the substrate, selectively adjust at least one of (i) the power applied to the first cathode, (ii) the power applied to the second cathode, (iii) the power applied to the anode, and (iv) the vertical position of the substrate holder.

[0025] In one aspect, the controller is further configured to, during the electrochemical deposition: detect a fault based on the first reflectivity of the substrate; and in response to the detection of the fault, display an indication of the fault on a display.

[0026] In one aspect, the controller is configured to: during the electrochemical deposition, determine an average value of a plurality of first reflectivities of the substrate, the first reflectivities of the substrate being measured during a rotation amount of the substrate; and during the electrochemical deposition, selectively adjust at least one of (i) the power applied to the first cathode, (ii) the power applied to the second cathode, (iii) the power applied to the anode, and (iv) the vertical position of the substrate holder based on the average value.

[0027] In one feature, the actuator is configured to move the first optical probe from a first distance from the center of the substrate to a second distance from the center of the substrate when the substrate is immersed in the electrolyte, where the second distance is different from the first distance. The controller is configured to selectively adjust, during the electrochemical deposition, at least one of (i) the power applied to the first cathode, (ii) the power applied to the second cathode, (iii) the power applied to the anode, and (iv) the vertical position of the substrate holder, based on a first value of the first reflectivity and a second value of the first reflectivity, where the first value of the first reflectivity is measured when the first optical probe is at the first distance from the center of the substrate, and the second value of the first reflectivity is measured when the first optical probe is at the second distance from the center of the substrate.

[0028] In one feature, the controller is configured to selectively adjust, during the electrochemical deposition, at least one of (i) the power applied to the first cathode, (ii) the power applied to the second cathode, (iii) the power applied to the anode, (iv) the vertical position of the substrate holder, (v) the angle of the substrate, and (vi) the distance between the first cathode and the second cathode, based on the first reflectivity of the substrate.

[0029] In one feature, an electrochemical deposition system includes: an electrochemical deposition chamber configured to hold an electrolyte for electrochemical deposition; a substrate holder including a first cathode; a first actuator configured to adjust the vertical position of the substrate holder in the electrochemical deposition chamber; an anode; a second cathode configured to be between the first cathode and the anode; and an optical probe configured to measure the reflectivity of the substrate during the electrochemical deposition.

[0030] In a further feature, the electrochemical deposition system includes a second optical probe configured to measure a second reflectivity of the substrate during the electrochemical deposition.

[0031] In a further feature, the optical probe includes: a light source configured to send light perpendicular to the surface of the substrate; and a light detector configured to receive light perpendicular to the surface of the substrate.

[0032] In a further feature, the optical probe includes: a light source configured to send light at an angle other than 90 degrees relative to the surface of the substrate; and a light detector configured to receive light at an angle other than 90 degrees relative to the surface.

[0033] In one feature, the electrochemical deposition system further includes a window portion located between the optical probe and the substrate, wherein the optical probe is configured to transmit and receive light passing through the window portion.

[0034] In a further feature, the optical probe includes: a light source configured to transmit light perpendicular to the surface of the substrate; and a light detector configured to receive light passing through the substrate.

[0035] In a further feature, the electrochemical deposition system further includes a bar, wherein the optical probe is positioned on the bar.

[0036] In a further feature, the optical probe is mounted to the wall of the electrochemical deposition chamber.

[0037] In a further feature, the optical probe is configured to transmit and receive light of only a single wavelength.

[0038] In a further feature, the optical probe is configured to transmit and receive light within a certain wavelength range.

[0039] In a further feature, the electrochemical deposition system further includes a second actuator configured to move the optical probe in at least one of the following movements: moving towards the center of the substrate and moving away from the center of the substrate.

[0040] Based on the detailed description, claims, and drawings, a further scope of applicability of the present disclosure will become apparent. The detailed description and specific examples are for illustrative purposes only and are not intended to limit the scope of the present disclosure. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] The present disclosure will be more fully understood from the detailed description and the drawings, wherein:

[0042] Figure 1 is a flowchart depicting an exemplary substrate processing method for manufacturing an integrated circuit;

[0043] Figures 2A - 2B is a functional block diagram of an exemplary implementation of an electrochemical deposition system;

[0044] Figure 3A depicts a first exemplary distance and an exemplary electric field between the substrate and the anode at the start of electrochemical deposition;

[0045] Figure 3B depicts a second exemplary distance and an exemplary electric field between the substrate and the anode closer to the end of electrochemical deposition;

[0046] Figure 4 An exemplary graph of substrate reflectivity versus the thickness of the material deposited on the substrate;

[0047] Figures 5 - 10 Including cross-sectional views that include example portions of a chamber, where the chamber includes one or more optical probes;

[0048] Figure 11 An exemplary graph of the normalized reflectivity at a location on the substrate as a function of electroplating time;

[0049] Figure 12A An exemplary graph of the normalized reflectivity at three different locations on the substrate as a function of electroplating time;

[0050] Figure 12B An exemplary graph of the normalized reflectivity at three different locations on the substrate as a function of electroplating time, where at least one of the current of the second cathode and the distance between the substrate and the anode is adjusted during electrochemical deposition;

[0051] Figure 13 A functional block diagram of an exemplary implementation of a system controller;

[0052] Figure 14 Including an exemplary graph depicting an exemplary interference where the incident light and the reflected light are perpendicular to the substrate, and an exemplary graph of the wavelength-averaged reflectivity as a function of time;

[0053] Figure 15 An exemplary graph of the relationship between the first reflectivity and time during electrochemical deposition;

[0054] Figure 16 An example of the rolling standard deviation of the first average reflectivity changing with time during electrochemical deposition;

[0055] Figure 17 Including a flowchart depicting an exemplary method of controlling the power applied to the first cathode, the second cathode, and the distance between the substrate and the anode during electrochemical deposition; and

[0056] Figures 18 - 24 Including cross-sectional views that include example portions of a chamber, where the chamber includes one or more optical probes.

[0057] In the drawings, reference numerals may be reused to identify similar and / or identical elements. Detailed Description

[0058] Electrochemical deposition can be used in a processing chamber to fill features formed in a dielectric layer of a substrate with a material (e.g., metal). The substrate contacts a first electrode. An anode is located at the bottom of the processing chamber. The electric field within the processing chamber can be varied by changing at least one of the following: (a) the distance between substrates, and (b) at least one of the power applied to the first electrode, the power applied to the second electrode, and the power applied to the anode. A trial-and-error method based on the substrate characteristics before and after deposition can be used to correct the target first cathode current distribution, the target second cathode current distribution, and the target distance distribution to be followed during electrochemical deposition.

[0059] According to the present disclosure, in-situ characteristics measured during deposition are used to improve thickness uniformity and improve the fill rate uniformity of the deposited material. For example, during deposition of a material on a substrate, one or more optical probes measure one or more reflectivities of the substrate. The reflectivity generally increases as the material (e.g., metal) is deposited on the substrate. The controller selectively adjusts the distance between substrates based on the one or more reflectivities. Additionally or alternatively, the controller can selectively adjust at least one of the following based on the one or more reflectivities: the power applied to the first electrode, the power applied to the second electrode, and the power applied to the anode. Closed-loop adjustment during deposition can improve thickness uniformity and improve the fill rate uniformity of the deposited material. Improving thickness uniformity and / or improving fill rate uniformity can reduce the total number of defects.

[0060] Figure 1 A flowchart depicting an exemplary substrate processing method for manufacturing an integrated circuit is shown. At operation 104, a dielectric layer is deposited on a substrate. At operation 108, features (e.g., trenches and / or vias) are formed in the dielectric layer, for example, by patterning and etching. At operation 112, a diffusion barrier is applied to the substrate, for example, by chemical vapor deposition (CVD) or physical vapor deposition (PVD).

[0061] At 116, a seed layer for the material (e.g., metal) is applied to the substrate. The seed layer can be applied, for example, via CVD or PVD. The seed layer can, for example, include titanium nitride, or another suitable seed material for the material. Examples of metals include metals such as copper, cobalt, tungsten, tin, silver, gold, ruthenium, titanium, tantalum, and oxides, nitrides, and alloys of these metals. At operation 120, the features are filled with the material. The features can be filled, for example, from the bottom of the feature to the top of the feature using electrochemical deposition. The electrochemical deposition is discussed further below. At operation 124, excess conductive material is removed, for example, by chemical mechanical planarization (CMP). Then, control can return to operation 104.

[0062] Figure 2AA functional block diagram of an exemplary implementation of an electrochemical deposition system 200, where the electrochemical deposition system 200 includes an electrochemical deposition chamber 204. The chamber 204 contains a bath of electrolyte 208 for depositing material (e.g., metal) within features formed in the lower surface 212 of a substrate 216. The electrolyte 208 may include ions of the material (e.g., metal) to be deposited on the substrate 216.

[0063] The substrate 216 is suspended from a substrate holder 218 that includes a first cathode 220. The first cathode 220 is in electrical contact with the outer edge of the substrate 216. For example, the first cathode 220 may include one or more clamping elements 224 (e.g., a plurality of gripping elements) to hold the substrate 216 to the substrate holder 218. The first cathode 220 may be made of a conductive material. The clamping elements 224 may also be made of a conductive material. The first cathode 220 may be in electrical contact with the outer edge of the substrate 216 via the clamping elements 224.

[0064] The substrate holder 218 may also include a second cathode 228 that is electrically isolated from the first cathode 220, for example, via an isolator 230. For example, the second cathode 228 may be an annular ring. The second cathode 228 may be made of a conductive material (e.g., platinum-plated titanium).

[0065] The anode 232 is immersed in the electrolyte 208 and is electrically isolated from the first cathode 220. The anode 232 may be fixed to the bottom surface of the chamber 204. The anode 232 may be made of a conductive material such as copper or cobalt.

[0066] A first actuator 236 raises and lowers the substrate holder 218. Thus, the first actuator 236 controls the distance between the substrate 216 and the anode 232. By way of example only, the first actuator 236 may include a linear actuator or other suitable type of actuator. Figure 2A An example is depicted where the first actuator 236 lowers the substrate 216 to a first position such that the substrate 216 is immersed in the electrolyte 208 for depositing material within features formed in the lower surface 212 of the substrate 216. Figure 2B An example is depicted where the first actuator 236 raises the substrate 216 to a second position such that the substrate 216 is not immersed in the electrolyte 208.

[0067] A second actuator 240 rotates the substrate holder 218. The second actuator 240 may include, for example, an electric motor to drive the substrate holder 218 to rotate at a rotational speed. The second cathode 228 may rotate with the substrate holder 218 or may not rotate when the substrate holder 218 rotates.

[0068] Power supply 250 applies power to first cathode 220, second cathode 228, and anode 232. The power applied to first cathode 220, second cathode 228, and anode 232, and the positions of first cathode 220 and second cathode 228 relative to anode 232 govern the shape of the electric field within chamber 204. System controller 260 controls the power applied to first cathode 220, second cathode 228, and anode 232 by power supply 250. System controller 260 also controls the distance between substrate 216 and anode 232 via first actuator 236. System controller 260 also controls the rotation of substrate holder 218 via second actuator 240.

[0069] Based on measurements obtained from one or more optical probes 264 within chamber 204, system controller 260 controls the distance between substrate 216 and anode 232, and the power applied to first cathode 220, second cathode 228, and anode 232. When substrate 216 is located within electrolyte 208, the one or more optical probes 264 measure, for example, the reflectivity of the lower surface 212 of substrate 216. Controlling the position and the applied power of first cathode 220 improves the thickness uniformity of the material deposited on substrate 216, and increases the fill rate uniformity across substrate 216.

[0070] The one or more optical probes 264 can be located on a horizontally extending bar 266 or tab. Bar 266 can be suspended from substrate holder 218. Bar 266 can rotate with substrate holder 218, or can be fixed and not rotate when substrate holder 218 rotates. Alternatively, bar 266 can be fixed, for example, to the wall of chamber 204.

[0071] Robot 270 can transport a substrate to substrate holder 218, or remove a substrate from substrate holder 218. For example, robot 270 can transfer a substrate to substrate holder 218, or transfer a substrate from substrate holder 218. System controller 260 can control the operation of robot 270.

[0072] Figure 3A And 3B Includes cross-sectional views depicting exemplary positions and electric fields during the electrochemical deposition of material within features of substrate 216. A first resistance of substrate 216 at the start of electrochemical deposition is higher than a second resistance of substrate 216 at the end of electrochemical deposition. As material (e.g., metal) is deposited on substrate 216, the resistance of substrate 216 gradually decreases.

[0073] Figure 3ADepicts a first exemplary distance and an exemplary electric field between the substrate 216 and the anode 232 at the start of electrochemical deposition. At the start of electrochemical deposition, near the location where the substrate 216 will make electrical contact at its edge, the electric field and current density will be naturally higher. The system controller 260 compensates for this by applying a first current to the second cathode 228, resulting in a more uniform electric field and current density towards the first cathode 220.

[0074] Figure 3B Depicts a second exemplary distance and an exemplary electric field between the substrate 216 and the anode 232 closer to the end of electrochemical deposition. At the end of electrochemical deposition, the resistance of the substrate 216 can be negligible. As the end of electrochemical deposition approaches, the system controller 260 can decrease or increase the distance between the substrate 216 and the anode 232 and reduce or terminate the current towards the second cathode 228. The adjusted distance and the reduced current towards the second cathode 228 result in a more uniform electric field and current density towards the first cathode 220.

[0075] Figure 4 Includes an exemplary graph of substrate reflectivity versus the thickness of the material deposited on the substrate. As shown, the reflectivity increases as the thickness of the material (e.g., metal) on the substrate increases. Once the material thickness is thick enough to completely reflect the incident electromagnetic radiation from one or more optical probes 264, the reflectivity reaches a steady state.

[0076] Figure 5 Includes a cross-sectional view that includes an example portion of the chamber 204. In various implementations, the one or more optical probes 264 can include two or more optical probes. For example, the first optical probe can include a first light source 504 and a first light detector 508. The first light source 504 and the first light detector 508 are configured to send and receive light from a first position near or at the outer edge of the substrate 216. The first light source 504 outputs light towards the substrate 216. The first light detector 508 receives the light from the first light source 504 and reflected by the substrate 216.

[0077] The second optical probe can include a second light source 512 and a second light detector 516. The second light source 512 and the second light detector 516 are configured radially inward from the first light source 504 and the first light detector 508. The second light source 512 and the second light detector 516 are configured to send and receive light from a second position, where the second position is radially inside the first position. The second position can be near or at the center of the substrate 216. The second light source 512 outputs light towards the substrate 216. The second light detector 516 receives the light from the second light source 512 and reflected by the substrate 216.

[0078] In various implementations, one or more other optical probes can be radially disposed between the first optical probe and the second optical probe. For example, a third optical probe can include a third light source 520 and a third light detector 524. The third light source 520 and the third light detector 524 are disposed radially inwardly from the first light source 504 and the first light detector 508 and radially outwardly from the second light source 512 and the second light detector 516. The third light source 520 and the third light detector 524 are configured to transmit and receive light from a third position, where the third position is radially outside the second position and radially inside the first position. The third light source 520 outputs light toward the substrate 216. The third light detector 524 receives light from the third light source 520 and reflected by the substrate 216.

[0079] A fourth optical probe can include a fourth light source 528 and a fourth light detector 532. The fourth light source 528 and the fourth light detector 532 are disposed radially inwardly from the third light source 520 and the third light detector 524 and radially outwardly from the second light source 512 and the second light detector 516. The fourth light source 528 and the fourth light detector 532 are configured to transmit and receive light from a fourth position, where the fourth position is radially outside the second position and radially inside the third position. The fourth light source 528 outputs light toward the substrate 216. The fourth light detector 532 receives light from the fourth light source 528 and reflected by the substrate 216.

[0080] A fifth optical probe can include a fifth light source 536 and a fifth light detector 540. The fifth light source 536 and the fifth light detector 540 are disposed radially inwardly from the fourth light source 528 and the fourth light detector 532, and radially outwardly from the second light source 512 and the second light detector 516. The fifth light source 536 and the fifth light detector 540 are configured to transmit and receive light from a fifth position, where the fifth position is radially outside the second position and radially inside the fourth position. The fifth light source 536 outputs light toward the substrate 216. The fifth light detector 540 receives light from the fifth light source 536 and reflected by the substrate 216.

[0081] In various implementations, one or more of the third, fourth, and fifth optical probes can be omitted. In various implementations, more than five optical probes can be included.

[0082] Based on the light rays reflected by the substrate 216 to the first, second, third, fourth, and fifth photodetectors 508, 516, 524, 532, and 540, the first, second, third, fourth, and fifth photodetectors 508, 516, 524, 532, and 540 generate and output signals. The outputs of the first, second, third, fourth, and fifth photodetectors 508, 516, 524, 532, and 540 respectively correspond to the reflectivities of the substrate 216 at the first, second, third, fourth, and fifth positions. Therefore, the outputs of the first, second, third, fourth, and fifth photodetectors 508, 516, 524, 532, and 540 respectively correspond to the material thicknesses deposited at the first, second, third, fourth, and fifth positions.

[0083] The first, second, third, fourth, and fifth light sources 504, 512, 520, 528, and 536 can send light rays perpendicular to the lower surface 212 of the substrate 216. The first, second, third, fourth, and fifth photodetectors 508, 516, 524, 532, and 540 can receive light rays perpendicular to the lower surface 212 of the substrate 216. In this example, both the incident (sent) and reflected light rays are perpendicular to the lower surface 212 of the substrate 216.

[0084] Figure 6 Includes a cross-sectional view that includes an exemplary portion of the chamber 204. In Figure 6 In the example, the first, second, third, and fourth light sources 504, 512, 520, and 528 send light rays at an angle other than 90 degrees with respect to the lower surface 212 of the substrate 216. The first, second, third, and fourth photodetectors 508, 516, 524, and 532 receive light rays at an angle other than 90 degrees with respect to the lower surface 212 of the substrate 216.

[0085] As shown, the first, second, third, and fourth light sources 504, 512, 520, and 528 send light rays to different positions on the substrate 216. For example, the first light source 504 sends light rays near the edge of the substrate 216, while the second light source 512 sends light rays to a location at or near the center of the substrate 216. The third light source 520 and the fourth light source 528 send light rays to positions between the edge and the center of the substrate 216.

[0086] Figure 7 Includes a cross-sectional view that includes an exemplary portion of the chamber 204. In various implementations, the window 704 can be located between the one or more optical probes and the substrate 216. In this example, the electrolyte 208 can be circulated above and below the window 704. The window 704 can be fixed to the wall of the chamber 204 or to the substrate holder 218.

[0087] Figure 8 Including a cross-sectional view that includes an exemplary portion of chamber 204. In various implementations, an optical probe can be fixed to the wall of chamber 204. The first, second, third, and fourth light sources 504, 512, 520, and 528 emit light at an angle other than 90 degrees relative to the lower surface 212 of substrate 216. The first, second, third, and fourth light detectors 508, 516, 524, and 532 receive light at an angle other than 90 degrees relative to the lower surface 212 of substrate 216.

[0088] As shown, the first, second, third, and fourth light sources 504, 512, 520, and 528 emit light to different locations on substrate 216. For example, the first light source 504 emits light to a first location near the edge of substrate 216, while the second light source 512 emits light to a second location at or near the center of substrate 216. The third light source 520 and the fourth light source 528 emit light to third and fourth locations between the edge and the center of substrate 216.

[0089] Figure 9 Including a cross-sectional view that includes an example portion of chamber 204. In various implementations, the first, second, third, and fourth light sources 504, 512, 520, and 528 emit light perpendicular to the lower surface 212 of substrate 216. The first, second, third, and fourth light sources 504, 512, 520, and 528 can emit light that passes through substrate 216 and the first cathode 220. The first, second, third, and fourth light detectors 508, 516, 524, and 532 can be disposed above the first cathode 220 and receive light from the first, second, third, and fourth light sources 504, 512, 520, and 528 that passes through substrate 216 and the first cathode 220. As the thickness of the material deposited at a location on substrate 216 increases, the light transmission through substrate 216 at that location decreases, thus reflecting more light (through the material). As the thickness of the material at the locations where the first, second, third, and fourth light sources 504, 512, 520, and 528 output light increases, the amount of light received by the first, second, third, and fourth light detectors 508, 516, 524, and 532 may decrease.

[0090] Figure 10 Including a cross-sectional view that includes an exemplary portion of chamber 204. In Figure 10In the example, the first light source 504 and the first light detector 508 move radially inwards and outwards. For example, the first light source 504 and the first light detector 508 may be located on the carriage 1004, and the carriage 1004 slides along the track within the bar 266. The actuator 1008 may push and pull the carriage 1004, thereby moving the first light source 504 and the first light detector 508 radially inwards and outwards. The actuator 1008 may move the first light source 504 and the first light detector 508 from the radially outer position to the radially inner position, and back to the radially outer position at a certain frequency.

[0091] The optical probe may be configured to transmit and receive light of only a single wavelength, or light within a certain wavelength range.

[0092] Figure 11 An exemplary graph of the normalized reflectance as a function of the electroplating time at a position on the substrate 216. As shown, the normalized reflectance is 0 at the beginning of the material deposition. As time goes by, the normalized reflectance increases. When the material deposition is completed, the normalized reflectance reaches 1.

[0093] Figure 12A An exemplary graph including the normalized reflectance as a function of the electroplating time at three different positions on the substrate 216. The trace 1204 records the normalized reflectance at a first position near the edge of the substrate 216 (e.g., measured by the first light detector 508 at a radius r = 135 mm from the center). The trace 1208 records the normalized reflectance at a second position near the center of the substrate 216 (e.g., measured by the second light detector 516 at a radius r = 15 mm from the center). The trace 1212 records the normalized reflectance at a third position between the first and second positions (e.g., measured by the fourth light detector 532 at a radius r = 95 mm from the center). As shown, the normalized reflectance rises and reaches 1 faster near the edge of the substrate 216 than near the center of the substrate 216.

[0094] Figure 12B An exemplary graph including the normalized reflectance as a function of the electroplating time at three different positions on the substrate 216, wherein at least one of the following is adjusted during the electrochemical deposition: the current of the second cathode 228, and the distance between the substrate 216 and the anode 232, as further discussed below. As shown, the deposition proceeds at approximately the same rate over the entire surface of the substrate 216. In other words, the filling rate over the entire substrate 216 is substantially uniform. Therefore, the substrate 216 may have a relatively uniform thickness of the deposited material.

[0095] Figure 13Functional block diagram of an exemplary implementation including system controller 260. Each time substrate holder 218 rotates, sampling module 1304 samples and digitizes the first reflectance measured by the first of the light detectors and the second reflectance measured by the second of the light detectors a number of times. By way of example only, sampling module 1304 may sample the first reflectance and the second reflectance at 40 equal intervals each time substrate holder 218 rotates, or at another suitable rate. During deposition of material on substrate 216, the first of the light detectors (e.g., second light detector 516) and the second of the light detectors (e.g., first light detector 508) receive light from different radial positions on substrate 216.

[0096] Averaging module 1308 averages the first reflectance measured over a period to determine a first average reflectance. The averaging module 1308 also averages the second reflectance measured over the period to determine a second average reflectance. The period may be, for example, one rotation of substrate holder 218, or another suitable period. The period may be moving or non-moving.

[0097] Error module 1312 determines the error between the first average reflectance and the second average reflectance. By way of example, error module 1312 may set the error based on the first average reflectance minus the second average reflectance, or set the error equal to the first average reflectance minus the second average reflectance. In Figure 10 the example of, error module 1312 may set the error to be based on or equal to the difference between the first reflectance measured by the first light detector 508 at a first time when the first light detector 508 is at a first radial position and the second reflectance measured by the first light detector 508 at a second time when the first light detector 508 is at a second radial position (which is different from the first radial position).

[0098] Filtering module 1316 filters the error one or more times to produce a filtered error. By way of example, based on the positions on substrate 216 associated with the first and second light detectors, filtering module 1316 may apply one or more weight values to (e.g., multiply) the error. The filtering module 1316 may additionally or alternatively apply a rate limit to changes in the error to smooth the filtered error.

[0099] Adjustment module 1320 selectively sets one or more adjustments based on the filtered error. For example, adjustment module 1320 can increase or decrease at least one of the following based on the filtered error: a first cathode adjustment, a second cathode adjustment, or a distance adjustment. The adjustment module 1320 adjusts at least one of the first cathode adjustment, the second cathode adjustment, or the distance adjustment to adjust the filtered error (and the error) towards zero. The first cathode adjustment can be used to vary the current of the first cathode 220 relative to the first cathode distribution. The first cathode distribution includes a series of power values applied to the first cathode 220 over time during the deposition of material on the substrate 216.

[0100] The first cathode control module 1324 controls the power applied to the first cathode 220 by the power supply based on the first cathode distribution and the first cathode adjustment. For example, the first cathode control module 1324 can multiply or add the value of the first cathode adjustment to the first cathode distribution and control the power applied to the first cathode 220 over time based on the result of the multiplication or addition.

[0101] The second cathode adjustment can be used to vary the current of the second cathode 228 relative to the second cathode distribution. The second cathode distribution includes a series of power values applied to the second cathode 228 over time during the deposition of material on the substrate 216.

[0102] The second cathode control module 1328 controls the power applied to the second cathode 228 by the power supply based on the second cathode distribution and the second cathode adjustment. For example, the second cathode control module 1328 can multiply or add the value of the second cathode adjustment to the second cathode distribution and control the power applied to the second cathode 228 over time based on the result of the multiplication or addition.

[0103] The distance adjustment can be used to vary the distance between the substrate 216 and the anode 232 relative to the distance distribution. The distance distribution includes a series of distances between the substrate and the anode 232 over time during the deposition of material on the substrate 216.

[0104] The distance control module 1332 drives the first actuator 236 based on the distance distribution and the distance adjustment. For example, the distance control module 1332 can multiply or add the value of the distance adjustment to the distance distribution and drive the first actuator 236 over time based on the result of the multiplication or addition.

[0105] During electrochemical deposition, adjusting the power applied to the first cathode 220, the power applied to the second cathode 228, and / or the distance between the substrate 216 and the anode 232 based on in-situ optical measurements using an optical probe can reduce the total number of defects in the substrate 216 and / or increase the uniformity of the deposited material. Although examples of the first and second reflectivities are provided, at least one of the first cathode adjustment, the second cathode adjustment, and the distance adjustment can be additionally or alternatively set based on one or more other pairs of reflectivities measured by one or more other pairs of photodetectors. Additionally, at least one of the first cathode adjustment, the second cathode adjustment, and the distance adjustment can be additionally or alternatively set based on more than two reflectivity signals. In an example of more than two reflectivity signals, the error module 1312 can weight each reflectivity signal to create the error.

[0106] Although examples of the distance between the substrate 216 and the anode 232 were discussed above, the geometry can be adjusted in one or more ways based on the error additionally or alternatively. For example, the system controller 260 can adjust the distance between the first cathode 220 and the second cathode 228, the position or size of one or more field shaping components (e.g., the first cathode 220, the second cathode 228, and / or the anode 232), and / or the angle of the substrate 216 in the electrolyte 208.

[0107] The endpoint module 1336 detects the endpoint of the electrochemical deposition based on at least one of these reflectivities (e.g., the first reflectivity) during the electrochemical deposition. For example, when the reflectivity intersects with the endpoint reflectivity, the rate of change of the reflectivity becomes smaller than the rate of change of the endpoint, or when the reflectivity reaches another suitable criterion, the endpoint module 1336 can detect the endpoint.

[0108] When the endpoint is detected, at least one of the first cathode control module 1324, the second cathode control module 1328, and the distance control module 1332 can adjust the power applied to the first cathode 220, the power applied to the second cathode 228, and the distance, respectively. For example, when the endpoint is detected, the first cathode control module 1324 can select a different first distribution. Additionally or alternatively, when the endpoint is detected, the second cathode control module 1328 can select a different second distribution. Additionally or alternatively, when the endpoint is detected, the distance control module 1332 can select a different distance distribution.

[0109] Although an example using an average reflectivity is shown, a non-average reflectivity can be used. Using a non-average reflectivity (e.g., a first reflectivity) can allow for the reflectivity of the substrate surface to be reflected for each rotation. This will provide a series of detailed snapshots that can be used to monitor the evolution (over time) of local differences in the reflectivity on substrate 216. This can be useful in cases where the substrate is initially more resistive and thus the material is more prone to faster deposition in lower resistance paths. These lower resistance paths can form at azimuthal positions on the edge of substrate 216 where nucleation starts stochastically earlier than other regions, or where the contact resistance is minimized. This can allow for real-time observation of path formation and allow for adjustment of at least one of these adjustments based on in-situ data from a light detector to avoid phenomena where path formation could potentially cause defects.

[0110] Fault module 1340 diagnoses the presence of one or more faults based on this first reflectivity during electrochemical deposition. When no faults are present, the reference distribution during electrochemical deposition includes a series of first reference reflectivities that vary over time. When the value of the first reflectivity at a given point in time is greater than or less than the first reference reflectivity at that point in time by at least a predetermined amount, fault module 1340 can diagnose the presence of a fault. Although an example using the first reflectivity is shown, fault module 1340 can additionally or alternatively diagnose the presence of a fault based on one or more other reflectivities.

[0111] When a fault is diagnosed, fault module 1340 can take one or more actions. For example, fault module 1340 can display a predetermined fault message on display 1344.

[0112] In an example where the light detector only detects a single light wavelength, the presence of interference fringes can be observed when a feature is filled from bottom to top. For example, when the average distance between the top reflective surface (e.g., unetched region) and the bottom reflective surface (etched region) is equal to or approximately equal to nλ / 4, destructive interference can occur, where n is an integer and λ is the wavelength of the light. When the average distance is equal to or approximately equal to nλ / 2, constructive interference can occur.

[0113] Figure 14 Includes an exemplary diagram depicting destructive interference when the average distance of this example is equal to nλ / 4, where the incident light and the reflected light are perpendicular to substrate 216. Figure 14 Also includes an exemplary diagram of the wavelength-averaged reflectivity as a function of time.

[0114] As Figure 13As shown, the average depth module 1350 can compare the average reflectivity distribution over time with the average reference reflectivity distribution over time to determine where constructive and destructive interference occur and thereby determine the depth of the feature. This can be performed for each sampled wavelength. This can improve the estimation of the average and standard deviation of the feature depth in the sample area.

[0115] The adjustment module 1320 can additionally or alternatively determine a first cathode adjustment based on the average depth. For example, the adjustment module 1320 can use a look-up table, and one of the equations that correlates the average depth with the first cathode adjustment to determine the first cathode adjustment. The adjustment module 1320 can additionally or alternatively determine a second cathode adjustment and / or a distance adjustment based on the average depth. Adjustments based on the average depth can remove the bias caused by azimuthal non-uniformity and can improve the signal-to-noise ratio for any variations in radial (e.g., center-to-edge) non-uniformity.

[0116] Figure 15 An exemplary graph including the first (non-average) reflectivity that changes over time during electrochemical deposition. Figure 16 An example including the rolling standard deviation of the first average reflectivity over time during electrochemical deposition. The endpoint module 1336 can detect the endpoint based on the first average reflectivity, the first reflectivity, or the rolling standard deviation of the first average reflectivity that becomes greater or smaller than their respective values.

[0117] Figure 17 Includes a flowchart depicting an exemplary method of controlling the power applied to the first cathode 220, the second cathode 228, and the distance between the substrate 216 and the anode 232 during electrochemical deposition. The control begins at operation 1704, where the first and second photodetectors 508 and 516 measure the first and second reflectivities of the substrate 216 at the first and second positions, respectively. As the substrate 216 rotates in the electrolyte 208, the first and second photodetectors 508 and 516 measure the first and second reflectivities, the first and second light sources 504 and 512 output light to the first and second positions, and the substrate 216 is held in the substrate holder 218.

[0118] At operation 1708, the averaging module 1308 determines the first and second average reflectivities. At operation 1712, the error module 1312 determines an error based on the difference between the second average reflectivity and the first average reflectivity. At operation 1716, the filtering module 1316 generates a filtered error based on the error. At operation 1720, the adjustment module 1320 determines a first cathode adjustment, a second cathode adjustment, and a distance adjustment based on the filtered error.

[0119] At operation 1724, during deposition, the first cathode control module 1324 selects a first value for the current time from a first distribution (for applying power to the first cathode 220). Similarly, during deposition, the second cathode control module 1328 selects a second value for the current time from a second distribution (for applying power to the second cathode 228). Similarly, during deposition, the distance control module 1332 selects a third value for the current time from a third distribution (for the distance between the substrate 216 and the anode 232).

[0120] At operation 1728, the first cathode control module 1324 controls the power applied to the first cathode 220 based on the first value and the first cathode adjustment. For example, the first cathode control module 1324 may apply power to the first cathode 220 that is based on or equal to (i) the first cathode adjustment plus the first value, or (ii) the first cathode adjustment multiplied by the first value. The second cathode control module 1328 controls the power applied to the second cathode 228 based on the second value and the second cathode adjustment. For example, the second cathode control module 1328 may apply power to the second cathode 228 that is based on or equal to (i) the second cathode adjustment plus the second value, or (ii) the second cathode adjustment multiplied by the second value. The distance control module 1332 controls the distance between the substrate 216 and the anode 232 based on the third value and the distance adjustment. For example, the distance control module 1332 may drive the first actuator 236 to achieve a distance that is based on or equal to (i) the distance adjustment plus the third value, or (ii) the distance adjustment multiplied by the third value.

[0121] At operation 1732, the system controller 260 may determine whether the deposition of material on the substrate 216 is complete. If operation 1732 is yes, the system controller 260 may deactivate the first cathode 220 and the second cathode 228. The system controller 260 may also remove the substrate 216 from the electrolyte 208. If operation 1732 is no, control may return to operation 1704.

[0122] Figure 18 A cross-sectional view of an electrochemical deposition system including an exemplary portion of the chamber 204. Figure 18In the example, chamber 204 is an electrochemical deposition chamber and is configured to hold electrolyte 208 for electrochemical deposition. Substrate holder 218 includes first cathode 220. First actuator 236 is configured to raise and lower substrate holder 218 to adjust the vertical position of substrate holder 218 within chamber 204. Chamber 204 may also include anode 232 and second cathode 228. Second cathode 228 is configured between first cathode 220 and anode 232. Optical probe 264 is configured to measure the reflectivity of substrate 216 during electrochemical deposition. Although an exemplary position of optical probe 264 is provided, optical probe 264 may be located in another suitable position.

[0123] Figure 19 A cross-sectional view of an electrochemical deposition system is shown, the electrochemical deposition system including Figure 18 An example portion of chamber 204 as shown in Figure 19 As shown in, includes a second one of optical probes 264. This second one of optical probes 264 is configured to measure a second reflectivity of the substrate during electrochemical deposition.

[0124] In Figure 18 optical probe 264 includes: a first light source 504 configured to send light perpendicular to the substrate surface; and a first light detector 508 configured to receive light perpendicular to the substrate surface.

[0125] Figure 20 A cross-sectional view of an electrochemical deposition system is shown, the electrochemical deposition system including Figure 18 An example portion of chamber 204 as shown in Figure 20 optical probe 264 includes: a first light source 504 configured to send light at an angle other than 90 degrees relative to the substrate surface; and a first light detector 508 configured to receive light at an angle other than 90 degrees relative to the surface.

[0126] Figure 21 A cross-sectional view of an electrochemical deposition system is shown, the electrochemical deposition system including Figure 18 An example portion of chamber 204 as shown in Figure 21 In the example of, window 704 is located between optical probe 264 and substrate 216. Optical probe 264 is configured to send and receive light passing through window 704.

[0127] Figure 22 A cross-sectional view of an electrochemical deposition system is shown, the electrochemical deposition system including Figure 18 An example portion of chamber 204 as shown in Figure 22In an example, the optical probe 264 includes: a first light source 504 configured to send light rays perpendicular to the surface of the substrate 216; and a first light detector 508 configured to receive the light rays passing through the substrate 216.

[0128] In Figure 18 an example, the optical probe 264 is located on the bar 266.

[0129] Figure 23 A cross-sectional view of an electrochemical deposition system including Figure 18 an example portion of the chamber 204 of Figure 23 In an example, the optical probe 264 includes a first light source 504 and a first light detector 508, and is mounted on the wall of the electrochemical deposition chamber 204.

[0130] In Figure 18 an example, the optical probe 264 is configured to send and receive light rays of only a single wavelength or light rays within a certain wavelength range.

[0131] Figure 24 A cross-sectional view of an electrochemical deposition system including Figure 18 an example portion of the chamber 204 of Figure 24 In an example, the second actuator 266 is configured to move the optical probe 264 toward and away from one of the centers of the substrate 216.

[0132] The foregoing description is merely illustrative in nature and is in no way intended to limit the present disclosure, its application, or uses. The broad teachings of the present disclosure can be implemented in a variety of forms. Thus, while the present disclosure includes specific examples, the true scope of the present disclosure should not be so limited because other modifications will become apparent upon study of the drawings, the specification, and the appended claims. It should be understood that one or more steps in a method can be performed in a different order (or simultaneously) without changing the principles of the present disclosure. Additionally, while each embodiment is described above as having certain features, any one or more of those features described with respect to any embodiment of the present disclosure can be implemented in and / or combined with the features of any other embodiment, even if the combination is not explicitly described. In other words, the described embodiments are not mutually exclusive, and permutations of one or more embodiments with each other remain within the scope of the present disclosure.

[0133] A variety of terms are used to describe the spatial and functional relationships between components (e.g., between modules, between circuit elements, between semiconductor layers, etc.), including terms such as "connected", "joined", "coupled", "adjacent", "next to", "on top of", "above", "below", and "disposed". Unless the relationship between the first and second components is explicitly described as "direct", when describing such a relationship in the above disclosure, the relationship can be a direct relationship where there are no other intermediate components between the first and second components, but it can also be an indirect relationship where there is one or more intermediate components between the first and second components (spatially or functionally). As used herein, the phrase "at least one of A, B, and C" should be construed to mean a logical (A or B or C) using non-exclusive logical OR, and should not be construed to mean "at least one of A, at least one of B, and at least one of C".

[0134] In some implementations, the controller is part of a system, which can be part of the above examples. Such systems can include semiconductor processing equipment, which includes one or more processing tools, one or more chambers, one or more platforms for processing, and / or specific processing components (wafer pedestals, gas flow systems, etc.). These systems can be integrated with electronics for controlling their operation before, during, and after the processing of semiconductor wafers or substrates. The electronics can be referred to as a "controller", which can control various components or sub-components of one or more systems. Depending on the processing requirements and / or system type, the controller can be programmed to control any of the processes disclosed herein, including the delivery of processing gases and / or liquids, temperature settings (e.g., heating and / or cooling), pressure settings, vacuum settings, power settings, radio frequency (RF) generator settings, RF matching circuit settings, frequency settings, flow rate settings, fluid delivery settings, position and operation settings, wafer transfer in and out of tools and other transfer tools, and / or load locks connected or interfaced to a particular system.

[0135] Broadly speaking, a controller can be defined as an electronic device having various integrated circuits, logic, memory, and / or software for receiving instructions, issuing instructions, controlling operations, enabling cleaning operations, enabling endpoint measurements, etc. The integrated circuits can include chips in the form of firmware that stores program instructions, digital signal processors (DSPs), chips defined as application-specific integrated circuits (ASICs), and / or one or more microprocessors, or microcontrollers that execute program instructions (e.g., software). The program instructions can be instructions sent to the controller in the form of various individual settings (or program files), and the individual settings (or program files) define the operating parameters for performing specific processes on or for a semiconductor wafer or system. In some embodiments, the operating parameters can be part of a recipe defined by a process engineer to complete one or more processing steps during the manufacture of one or more layers, materials, metals, oxides, silicon, silicon dioxide, surfaces, circuits, and / or die of a wafer.

[0136] In some implementations, the controller can be part of or coupled to a computer that is integrated with, coupled to, otherwise networked to, or a combination of the system. For example, the controller can be in the "cloud" or be all or part of a wafer fab host system, which can allow remote access to wafer processing. The computer can enable remote access to the system to monitor the current progress of manufacturing operations, review the history of past manufacturing operations, review trends or performance criteria of multiple manufacturing operations, change the parameters of the current process, set processing steps to follow the current process, or initiate a new process. In some examples, a remote computer (e.g., a server) can provide a processing recipe to the system via a network, which can include a local network or the Internet. The remote computer can include a user interface that enables the input or programming of parameters and / or settings, which are then sent from the remote computer to the system. In some examples, the controller receives instructions in the form of data that specify the parameters for each processing step to be performed during one or more operations. It should be understood that the parameters can be specific to the type of process to be performed and the type of tool that the controller is configured to interface with or control. Thus, as described above, the controller can be distributed, for example, by including one or more discrete controllers networked together and working towards a common purpose (e.g., the processing and control described herein). An example of a distributed controller for such a purpose is one or more integrated circuits on a chamber that communicate with one or more integrated circuits remotely (e.g., at the platform level or as part of a remote computer), which combine to control the processing on the chamber.

[0137] Example systems can include, but are not limited to, a plasma etch chamber or module, a deposition chamber or module, a spin rinse chamber or module, a metal electroplating chamber or module, a cleaning chamber or module, a bevel edge etch chamber or module, a physical vapor deposition (PVD) chamber or module, a chemical vapor deposition (CVD) chamber or module, an atomic layer deposition (ALD) chamber or module, an atomic layer etch (ALE) chamber or module, an ion implantation chamber or module, an orbit chamber or module, and any other semiconductor processing system that can be associated with and / or used in the manufacture and / or preparation of semiconductor wafers.

[0138] As described above, depending on one or more processing steps to be performed by a tool, the controller can communicate with one or more other tool circuits or modules, other tool components, cluster tools, other tool interfaces, adjacent tools, neighboring tools, tools located throughout a factory, a host computer, another controller, or tools used in a material transport that shuttles a wafer container between a tool location and / or load port in a semiconductor manufacturing factory.

Claims

1. An electrochemical deposition system, which comprises: an electrochemical deposition chamber including an electrolyte for electrochemical deposition; a substrate holder configured to hold a substrate and including a first cathode electrically connected to the substrate; a first actuator configured to adjust a vertical position of the substrate holder in the electrochemical deposition chamber; an anode immersed in the electrolyte; a second cathode configured to be between the first cathode and the anode; a first optical probe configured to measure a first reflectivity of the substrate at a first distance from a center of the substrate during the electrochemical deposition when the substrate is immersed in the electrolyte; and a controller configured to selectively adjust at least one of (i) power applied to the first cathode, (ii) power applied to the second cathode, (iii) power applied to the anode, and (iv) the vertical position of the substrate holder based on the first reflectivity of the substrate during the electrochemical deposition.

2. The electrochemical deposition system according to claim 1, which further comprises: a second optical probe configured to measure a second reflectivity of the substrate at a second distance from the center of the substrate during the electrochemical deposition when the substrate is immersed in the electrolyte, wherein the controller is configured to further selectively adjust at least one of (i) the power applied to the first cathode, (ii) the power applied to the second cathode, (iii) the power applied to the anode, and (iv) the vertical position of the substrate holder based on the second reflectivity of the substrate during the electrochemical deposition.

3. The electrochemical deposition system according to claim 2, wherein the first distance is different from the second distance.

4. The electrochemical deposition system according to claim 2, wherein the controller is configured to selectively adjust at least one of (i) the power applied to the first cathode, (ii) the power applied to the second cathode, (iii) the power applied to the anode, and (iv) the vertical position of the substrate holder based on a difference between the first reflectivity and the second reflectivity during the electrochemical deposition.

5. The electrochemical deposition system according to claim 4, wherein the controller is configured to during the electrochemical deposition: determine a first cathode adjustment based on a filtered error, where the filtered error is generated by filtering the difference one or more times by a filtering module, and the first cathode adjustment is an adjustment of the power applied to the first cathode; and apply power to the first cathode based on the first cathode adjustment and a value selected from a first cathode distribution, where the first cathode distribution includes a series of power values applied to the first cathode over time during deposition of material on the substrate.

6. The electrochemical deposition system according to claim 4, wherein the controller is configured to, during the electrochemical deposition: Determine a second cathode adjustment based on a filtered error, wherein the filtered error is generated by filtering the difference one or more times by a filtering module, and wherein the second cathode adjustment is an adjustment of the power applied to the second cathode; and Apply power to the second cathode based on the second cathode adjustment and a value selected from a second cathode distribution, wherein the second cathode distribution includes a series of power values applied to the second cathode over time during deposition of the material on the substrate.

7. The electrochemical deposition system according to claim 4, wherein the controller is configured to, during the electrochemical deposition: Determine a distance adjustment based on a filtered error, wherein the filtered error is generated by filtering the difference one or more times by a filtering module, and wherein the distance adjustment is an adjustment of the distance between the substrate and the anode; and Adjust the vertical position of the substrate holder based on the distance adjustment and a value selected from a distance distribution, wherein the distance distribution includes a series of distances between the substrate and the anode over time during deposition of the material on the substrate.

8. The electrochemical deposition system according to claim 1, wherein the first optical probe Comprises: A first light source configured to emit light perpendicular to the surface of the substrate during the electrochemical deposition when the substrate is immersed in the electrolyte; And A first light detector configured to receive light perpendicular to the surface of the substrate during the electrochemical deposition when the substrate is immersed in the electrolyte.

9. The electrochemical deposition system according to claim 1, wherein the first optical probe Comprises: A first light source configured to emit light at an angle other than 90 degrees with respect to the surface of the substrate during the electrochemical deposition when the substrate is immersed in the electrolyte; And A first light detector configured to receive light at an angle other than 90 degrees with respect to the surface during the electrochemical deposition when the substrate is immersed in the electrolyte.

10. The electrochemical deposition system according to claim 1, further comprising a window located between the first optical probe and the substrate, Wherein the first optical probe is configured to emit and receive light passing through the window during the electrochemical deposition when the substrate is immersed in the electrolyte.

11. The electrochemical deposition system according to claim 1, wherein the first optical probe Comprises: A first light source configured to emit light perpendicular to the surface of the substrate during the electrochemical deposition when the substrate is immersed in the electrolyte; And A first light detector configured to receive light passing through the substrate during the electrochemical deposition when the substrate is immersed in the electrolyte.

12. The electrochemical deposition system according to claim 1, further comprising a bar, wherein the first optical probe is located on the bar.

13. The electrochemical deposition system according to claim 1, wherein the first optical probe is mounted to the wall of the electrochemical deposition chamber.

14. The electrochemical deposition system according to claim 1, wherein the first optical probe is configured to transmit and receive light of only a single wavelength.

15. The electrochemical deposition system according to claim 1, wherein the first optical probe is configured to transmit and receive light within a certain wavelength range.

16. The electrochemical deposition system according to claim 1, further comprising a second actuator configured to rotate the substrate holder during the electrochemical deposition.

17. The electrochemical deposition system according to claim 1, wherein the controller is further configured during the electrochemical deposition: Detect an end point of the electrochemical deposition based on the first reflectivity of the substrate; and In response to the detection of the end point, selectively adjust at least one of (i) the power applied to the first cathode, (ii) the power applied to the second cathode, (iii) the power applied to the anode, and (iv) the vertical position of the substrate holder.

18. The electrochemical deposition system according to claim 1, wherein the controller is further configured during the electrochemical deposition: Determine a depth of a feature formed in the substrate based on the first reflectivity of the substrate; and Based on the depth of the feature formed in the substrate, selectively adjust at least one of (i) the power applied to the first cathode, (ii) the power applied to the second cathode, (iii) the power applied to the anode, and (iv) the vertical position of the substrate holder.

19. The electrochemical deposition system according to claim 1, wherein the controller is further configured during the electrochemical deposition: Detect a fault based on the first reflectivity of the substrate; and In response to the detection of the fault, display an indication of the fault on a display.

20. The electrochemical deposition system according to claim 1, wherein the controller is configured to: During the electrochemical deposition, determine an average value of a plurality of first reflectivities of the substrate, the first reflectivities of the substrate being measured during a rotation amount of the substrate; and During the electrochemical deposition, selectively adjust at least one of (i) the power applied to the first cathode, (ii) the power applied to the second cathode, (iii) the power applied to the anode, and (iv) the vertical position of the substrate holder based on the average value.

21. The electrochemical deposition system according to claim 1 further includes an actuator configured to move the first optical probe from a first distance from the center of the substrate to a second distance from the center of the substrate when the substrate is immersed in the electrolyte, where the second distance is different from the first distance. Wherein the controller is configured to selectively adjust at least one of (i) the power applied to the first cathode, (ii) the power applied to the second cathode, (iii) the power applied to the anode, and (iv) the vertical position of the substrate holder during the electrochemical deposition, based on a first value of the first reflectivity and a second value of the first reflectivity, where the first value of the first reflectivity is measured when the first optical probe is at the first distance from the center of the substrate, and the second value of the first reflectivity is measured when the first optical probe is at the second distance from the center of the substrate.

22. The electrochemical deposition system according to claim 1, wherein the controller is configured to selectively adjust at least one of (i) the power applied to the first cathode, (ii) the power applied to the second cathode, (iii) the power applied to the anode, (iv) the vertical position of the substrate holder, (v) the angle of the substrate, and (vi) the distance between the first cathode and the second cathode during the electrochemical deposition, based on the first reflectivity of the substrate.

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