TW201632660A - Electroplating apparatus and method - Google Patents

Abstract

An apparatus and a method for plating a substrate are provided. The apparatus includes: an electroplating cell for containing an electroplating solution; a substrate holder for holding a substrate in the electroplating solution; a rotation driver coupled to the substrate holder and configured to rotate the substrate holder; a power distribution assembly coupled to the rotation driver; an anode disposed within the electroplating cell; a power supply unit electrically coupled between the anode and the power distribution assembly, thereby forming an electric loop; and a current regulating member for providing a predetermined impedance value for the electric loop, wherein a voltage provided by the power supply unit causes an electric current to flow through the electric loop, and the predetermined impedance is such selected that the variation of the electric current is kept within a smaller range compared to that measured in the absence of the current regulating member.

Description

Plating equipment and methods

The present disclosure is directed to a method and apparatus for electrochemically plating a semiconductor structure.

A semiconductor device is an electronic component that utilizes semiconductor materials and electrical characteristics of an organic semiconductor. In most applications, semiconductor devices have replaced thermionic elements (vacuum tubes). Semiconductor devices utilize electron conduction in the solid state rather than thermionic emission caused by gas or high vacuum. The semiconductor device can be fabricated as a separate single component or integrated circuit (IC) consisting of a plurality of components fabricated and interconnected on a single semiconductor substrate or wafer.

The fabrication of semiconductor devices is a multi-step process consisting of multiple light and shadow processes, in which electronic circuits are progressively formed on wafers made of pure semiconductor materials. Coffins are commonly used in most cases, but a variety of composite semiconductors can be used in certain applications. In various semiconductor fabrication processes, a layer deposition process is used to form the IC components. One of the most commonly used layer deposition processes is an electro-chemical plating (ECP) process that deposits a layer of conductive material onto a substrate by electrolytic deposition.

One of the problems with conventional electroplating equipment is that the physical properties, dimensional conditions, or other parameters associated with the various components in the electrical loop can cause significant variations in the current flowing through the electrical loop, thus affecting the quality and uniformity of the plating.

Some embodiments of the present disclosure provide an electroplating apparatus capable of electroplating a substrate, comprising: a plating bath for accommodating a plating solution; and a substrate holder for holding a substrate in the plating solution; The rotary driver is electrically coupled to the substrate holder and is configured to rotate the substrate holder; a power distribution component is electrically coupled to the rotary driver; an anode is disposed in the plating tank, and the anode is immersed in the plating solution; a power supply unit is electrically coupled between the anode and the power distribution component, thereby forming an electrical circuit; and a current regulating structure for providing a predetermined impedance value to the electrical circuit, wherein the power supply unit provides The voltage causes a current to flow through the electrical loop, and the predetermined impedance is selected such that the variation of the current flowing through the electrical loop is maintained in a smaller range compared to the condition without the current modulating member The current is mutated.

Some embodiments of the present disclosure provide an electroplating apparatus capable of electroplating a substrate, comprising: a plating bath for accommodating a plating solution; and a substrate holder for holding a substrate in the plating solution; The rotary driver is electrically coupled to the substrate holder and is configured to rotate the substrate holder; an anode is disposed in the plating bath, and the anode is immersed in the plating solution, wherein a voltage applied to the rotary driver and the anode causes a current to be a rotary actuator flows to the anode; and a current-regulating structure electrically coupled to the rotary driver, wherein the predetermined impedance value of one of the current-regulating structures is selected such that the variation of the current is maintained in a smaller range, as compared to The current variation measured under the condition of the current modulating structure.

Some embodiments of the present disclosure provide an electroplating method for electroplating a substrate, comprising: immersing a substrate in a plating solution; electrically coupling an anode to the plating solution; forming an electrical circuit, wherein a current flows from the power supply to the anode, the plating solution, the substrate, and back to the power supply; and a current modulating structure having a predetermined impedance value is provided on the electrical circuit, wherein the predetermined impedance is selected to flow through the electrical The current variation of the current of the loop is maintained in a small range compared to the measured current variability in the absence of a current-regulating structure, wherein the current flows in the electrical loop A conductive material is deposited on the substrate.

100, 200, 300, 600, 700‧‧‧ plating equipment

101‧‧‧ plating bath

102‧‧‧ plating solution

102a‧‧‧ surface

103‧‧‧Substrate holder

103a‧‧‧Cone member

103b‧‧‧Cup member

103c‧‧‧ Sealing (flange) components

104‧‧‧Substrate

104a‧‧‧ plating surface

105‧‧‧Rotary drive

105a‧‧‧Rotatable mandrel

105b‧‧‧slip ring assembly

106‧‧‧Power distribution components

107‧‧‧Anode

108‧‧‧Power supply unit

109‧‧‧current adjustment structure

801, 802, 803, 804‧‧‧ operations

I1, I2, I3, I4‧‧‧ current

V‧‧‧ voltage

The various aspects of the present disclosure can be best understood upon reading the following description and the accompanying drawings. It should be noted that the various components in the figures are not drawn to scale in accordance with standard practice in the art. In fact, in order to be able to clearly describe, it is possible to intentionally enlarge or reduce the size of certain components.

Figure 1 is a schematic diagram showing an electroplating apparatus for electrochemically plating a substrate in an electrochemical plating (ECP) process.

2 is a schematic view of an electroplating apparatus for electrochemically plating a substrate in accordance with an embodiment of the present disclosure.

FIG. 3 is a schematic view showing an electroplating apparatus according to an embodiment of the present disclosure.

4 is a cross-sectional view showing a substrate holder and a rotary actuator according to an embodiment of the present disclosure.

5 is a cross-sectional view showing a substrate holder and a rotary actuator according to an embodiment of the present disclosure.

Figure 6 is a schematic diagram showing an electroplating apparatus for electroplating a substrate.

FIG. 7 is a schematic view showing an electroplating apparatus for electrochemically plating a substrate according to an embodiment of the present disclosure.

Figure 8 is a flow chart of a method for electroplating a substrate.

The manner of manufacture and use of embodiments of the present disclosure is described in detail below. However, it is conceivable that these embodiments provide a number of achievable inventive concepts and can be implemented in a wide variety of specific contexts. It is to be understood that the following disclosure provides various embodiments or illustrations that can be used to implement various features of the present disclosure. Below Specific examples of components and configurations are included to simplify the disclosure. These narratives are merely illustrative and are not intended to limit the disclosure.

The specific text is used below to illustrate the embodiments or embodiments illustrated in the drawings. However, it should be understood that these embodiments and embodiments are not intended to be limiting. Any alterations and modifications of the described embodiments, as well as any further application of the principles described in the present document, are within the scope of the ordinary skill in the art to which the invention pertains.

Furthermore, it will be appreciated that certain process steps (operations) and/or features of the components may be described briefly. Again, additional process steps and/or features may be added and some subsequent process steps and/or steps may be removed or altered, but the claimed invention may still be implemented. Therefore, the following description is to be construed as illustrative only and not as a limitation

In addition, element symbols and/or labels may be reused in various embodiments in the present disclosure. This repetition is for the sake of brevity and clarity and is not intended to limit the relationship between the various embodiments and/or configurations discussed.

Furthermore, the use of spatially relative vocabulary, such as "below", "below", "below", "above", "above" and similar, may be used to facilitate the illustration. The relationship between one element or member shown relative to another element or elements. These spatially relative terms are intended to encompass a variety of different orientations of the device in use or operation, in addition to the orientation depicted in the Figures. It is possible to place the device in other orientations (eg, rotated 90 degrees or in other orientations), and these spatially relative descriptive words should be interpreted accordingly.

When an integrated circuit (IC) is prepared, a plurality of process steps are performed on a semiconductor. In these steps, a layer deposition process is utilized to form an IC component such as a polysilicon gate material and a metal interconnect layer in the dielectric layer cavity. The deposition process includes physical vapor deposition (PVD) and atomic layer deposition. (atomic layer deposition, ALD) and electro-chemical plating (ECP).

An electrochemical plating (ECP) process deposits a layer of electrically conductive material onto a substrate by electrolytic deposition, wherein the substrate is immersed in a plating solution containing a plurality of ions of the material to be deposited. A DC voltage is applied to the substrate such that it acts as a cathode to attract cations in the plating solution. These cations are reduced and accumulated on the substrate to form a thin film on the substrate.

Referring to the drawings, the schematic of Figure 1 illustrates an electroplating apparatus 100 for electrochemically plating a substrate in an electrochemical plating (ECP) process. The electroplating apparatus 100 includes a plating bath 101, a substrate holder 103, a rotary driver 105, a power distribution assembly 106, and an anode 107. The plating bath 101 serves as a container/ware that can accommodate the plating solution 102. The substrate holder 103 is used to hold the substrate 104 in the plating solution 102. The rotary driver 105 is used to rotate the substrate holder 103 and is electrically coupled to the substrate holder 103. The power distribution component 106 is electrically coupled to the rotary driver 105. Further, the anode 107 is provided in the plating tank 101, and the anode 107 is immersed in the plating solution 102. The electroplating apparatus 100 further includes a power supply unit 108 electrically coupled between the anode 107 and the power distribution component 106, thereby forming an electrical loop (not shown). The power supply unit 108 is configured to provide a voltage V (not shown) such that the current I1 flows through the electrical circuit. That is, the current I1 flows from the power supply unit 108 through the anode 107, the plating solution 102, the substrate 104, the substrate holder 103, the rotary driver 105, the power distribution assembly 106, and returns to the power supply unit 108. The flow of current I1 in the electrical circuit causes deposition of conductive material (not shown) in the plating solution 102 onto the substrate 104.

As is well known to those skilled in the art, in electrochemical electroplating (ECP) processes, plating quality and uniformity depend on the stability and uniformity of the current distribution. Assuming that the voltage V provided by the power supply unit 108 is a fixed value, the current I1 depends on the total effective impedance of the electrical circuit, which includes the substrate 104, the substrate holder 103, the rotary driver 105, The power distribution component 106, the power supply unit 108, the anode 107, the conductive path of the plating solution 102 (from the anode 107 to the substrate 104), and the effective impedance of the conductive line. Therefore, one of the problems faced by the conventional electroplating apparatus 100 is that the physical characteristics, dimensional conditions, or other parameters of various components (eg, the substrate 104) in the electrical circuit cause significant variations in the current I1 flowing through the electrical loop. This in turn affects plating quality and uniformity.

What is more, when the current flowing through the electrical circuit of the electroplating device is significantly mutated, other problems may occur in the electroplating process of the semiconductor substrate (or wafer). In general, the electroplating apparatus does not perform the electroplating process until the substrate is completely immersed in the plating solution. During the pre-plating step (defined as the period from the time the substrate is immersed in the plating bath to the full immersion), the current will gradually increase to a peak current value (as the resistance/impedance between the substrate/plating solution interface increases) small). Therefore, the detection of the peak current value can be utilized as an indicator for completely immersing the substrate into the plating solution for subsequent plating operations. In view of this, a significant current variation in the electrical circuit (due to, for example, wafer-to-wafer variation) can cause significant variations in peak current values, which in turn can affect plating quality or Reduce throughput.

In order to solve the above problems in the conventional plating apparatus 100, an electroplating apparatus having an additional current regulating structure is proposed herein. 2 is a schematic diagram of an electroplating apparatus 200 for electrochemically plating a substrate in accordance with an embodiment of the present disclosure. Similarly, electroplating apparatus 200 includes a plating bath 101, a substrate holder 103, a rotary driver 105, a power distribution assembly 106, an anode 107, a power supply unit 108, and a current modulating structure 109. The plating bath 101 can accommodate the plating solution 102, and the substrate holder 103 is used to hold the substrate 104. The power supply unit 108 may be a DC power supply unit. According to the configuration shown in FIG. 2 , the current regulating structure 109 is electrically coupled between the rotary driver 105 and the power distribution component 106 . However, it can be noted that the current modulating structure 109 can also be placed at other locations on the electrical circuit. For example, in FIG. 3 (which is a schematic diagram of a plating apparatus 300 according to an embodiment of the present disclosure), the current regulating structure 109 is electrically coupled to a power supply. Between the unit 108 and the anode 107. Alternatively, the current modulating structure 109 can be electrically coupled between the power supply unit 108 and the power distribution component 106. Alternatively, the current regulating structure 109 can be electrically coupled between the substrate holder 103 and the rotary driver 105. It should be noted that the current modulating structure 109 should not be disposed in the plating bath 101.

Referring back to FIG. 2, the voltage V provided by the power supply unit 108 causes the current I2 to flow through the electrical circuit, wherein the current I2 flows from the power supply unit 108 through the anode 107, the plating solution 102, the substrate 104, the substrate holder 103, The drive 105, the current regulating structure 109, and the power distribution assembly 106 are rotated and returned to the power supply unit 108. The flow of current I2 in the electrical circuit causes the conductive material in the plating solution 102 to deposit onto the substrate 104.

The function of the current modulating structure 109 is to provide a predetermined impedance value to the electrical circuit. The predetermined impedance is selected such that the variation of the current I2 flowing through the electrical loop is maintained in a small range compared to the current I1 flowing through the electrical loop (where the current variation is in the absence of a current-regulating structure) Measured under conditions of 109). The choice of the predetermined impedance depends on the following two criteria: (1) the greater the impedance of the current-modulating structure 109, the easier it is to control the variation of the current flowing through the electrical loop; and (2) the impedance of the current-regulating structure 109. The larger the power, the higher the power it consumes. In a preferred case, the predetermined impedance value ranges between 0.02 mΩ and 20 Ω. In a more preferred case, the predetermined impedance value ranges between 0.05 mΩ and 5 Ω. In a still more preferred case, the predetermined impedance value ranges between 0.1 mΩ and 1 Ω. In the best case, the predetermined impedance value is 50 mΩ. It should be noted that the total impedance of the electrical circuit ranges from 1 Ω to 50 Ω.

In one embodiment, the substrate 104 is a semiconductor wafer having conductive features/members (eg, conductive plugs, conductive vias, conductive posts, fillers, or conductive traces) on the active surface (plated surface). In an embodiment, the substrate 104 may include or be similar to a logic element, an embedded flash memory (eFlash) element, a memory element, a microelectromechanical (MEMS) element, a digital element, a CMOS element, or a combination thereof. By. Substrate 104 may include doped or undoped germanium blocks An active layer of a silicon-on-insulator (SOI) substrate. In general, the SOI substrate includes a layer of semiconductor material such as germanium, germanium, germanium, SOI, silicon germanium on insulator (SGOI), or a combination thereof. In one embodiment, the substrate 104 includes a multilayer substrate, a gradient substrate, a mixed direction substrate, any combination of the above, and/or the like, such that the semiconductor package can accommodate more active and passive components and circuits. In one embodiment, the substrate 104 is electroplated using an electroplating apparatus 200 to form a plurality of copper interconnects, patterns, or layers on a semiconductor component that has previously been disposed on the active surface of the substrate 104.

In one embodiment, the conductive material used for electroplating onto the substrate 104 can be a metal (such as gold, zinc nickel, silver, copper, or nickel), and the anode 107 can be made of the same metal. Further, the plating solution 102 may include metal salts of the same metal. In one embodiment, the conductive material to be deposited/plated onto the substrate 104 is copper. Therefore, the anode 107 can be made of copper. The plating bath 102 can be a mixture comprising salts of copper, acids, water, and various organic and inorganic additives that improve the deposition characteristics of copper. Copper salts suitable as the plating solution 102 include copper sulfate, copper cyanide, copper sulfonate, copper chloride, copper formate, copper fluoride, copper nitride, copper oxide, copper fluoroborate, copper trifluoroacetate, Copper pyrophosphate and copper methanesulfonate, or a hydrate of any of the above compounds. The concentration of the copper salt in the plating solution 102 will vary depending on the type of copper salt used. Various acids useful in the plating bath 102 include: sulfuric acid, methanesulfonic acid, fluoroboric acid, hydrochloric acid, nitric acid, phosphoric acid, and other suitable acids. The concentration of the acid in the plating solution 102 varies depending on the kind of the acid to be used.

In one embodiment, the plating solution 102 is a copper sulfate (CuSO ₄ ) solution. Both the substrate 104 and the anode 107 are immersed in a plating solution 102 (CuSO ₄ solution) containing one or more dissolved metal salts and other ions that allow current to flow therethrough. The power supply unit 108 supplies a current to the anode 107, oxidizing the copper atoms contained in the anode 107 and dissolving it in the plating solution 102. On the substrate 104 (cathode), metal ions (cationic Cu ²⁺ ) dissolved in the plating solution 102 are reduced to metallic copper by obtaining two electrons on the substrate 104. At the anode 107, copper is oxidized to Cu ²⁺ at the anode by losing two electrons. As a result, copper is transferred from the anode 107 to the substrate 104. The rate at which the anode 107 dissolves is equal to the rate at which the substrate 104 is plated. As such, the anode 107 can continue to replenish ions in the plating solution 102.

The plating solution 102 can include certain additives that can improve certain plating characteristics of the plating solution, improve the characteristics of the deposited copper, or accelerate the deposition rate of copper. One of the primary functions of the additive is to make the deposit flatter by inhibiting the rate of electrodeposition of the raised regions in the surface of the substrate 104 and/or accelerating the rate of electrodeposition of the recessed regions in the surface of the substrate 104. Absorption and inhibition can be further enhanced by the presence of halogen ions.

Common additives for copper plating baths include brighteners, suppressors, and levelers. Brighteners are organic molecules that improve the unidirectional reflectivity of copper deposits by reducing surface roughness and particle size variation. Suitable brighteners include, for example, organic Sulfur compounds, such as sodium bis-(sodium sulfopropyl-disulfide), 3-mercapto-1-propanesulfonic acid sodium salt, N-di N-dimethyl-dithiocarbamyl propylsulfonic acid sodium salt and 3-S-isothiurium propyl sulfonate or a combination of any of the above compounds . Inhibitors are macromolecular deposition inhibitors that are capable of being absorbed by the upper surface of the substrate and that reduce local deposition rates and increase deposition uniformity. The balance agent typically contains a component with a nitrogen functional group and its content in the plating bath is generally relatively low. Conventional balancing agents involve diffusing or migrating substances with strong current-suppressing forces to the corners or edges of macroscopic objects that would otherwise be affected by electric fields and mass transfer effects. Plating at a higher rate than desired. The balancing agent may be selected from the group consisting of polyether surfactants, nonionic surfactants, cationic surfactants, anionic surfactants, block copolymer surfactants, polyethylene glycol surfactants, polyacrylic acid, poly Amine, aminocarboxylic acid, hydroxycarboxylic acid, citric acid, N,N,N',N'-tetra-(2-hydroxypropyl)ethylenediamine (entprol), ethylenediaminetetraacetate, tartaric acid, quaternized polyamine, polypropylene decylamine, cross聚聚醯amine, phenazine azo-dye, alkoxylated amine surfactant, polymer pyridine derivative, polyethyleneimine, polyethyleneimine ethanol, oxazoline and A polymer of epichlorohydrine and a benzylated polyamine polymer.

Another method for uniformly depositing metal ions (from plating solution 102) on substrate 104 is to agitate plating solution 102 to cause plating solution 102 to flow to substrate 104 at a uniform flow rate. In the electroplating process, a uniform flow rate is important for uniformly depositing metal ions from the plating solution 102 onto the substrate 104. In one embodiment, the flow rate of the plating solution 102 to the center of the plating surface of the substrate 104 is controlled to be equal to the flow velocity to the periphery of the plating surface of the substrate 104. Therefore, the flow rates of the plating solution 102 (when it flows laterally through the plating surface of the substrate 104) are uniform, and a uniform plating height can be obtained. In addition, uneven plating thickness due to uneven distribution of the flow rate of the plating solution can be alleviated, and a uniform plating thickness distribution can be obtained on the plating surface of the substrate 104.

4 is a cross-sectional view showing a substrate holder 103 and a rotary driver 105 according to an embodiment of the present disclosure. The substrate holder 103 can be controlled to hold the substrate 104 and immerse it into the plating solution 102. In an embodiment, the substrate holder 103 may be a clamshell substrate holder including a tapered member 103a, a cup member 103b and a sealing member (flange) member 103c, wherein the cup member 103b and the sealing member 103c The outer shape is in a ring shape. When the substrate 104 is clamped in the cavity formed by the tapered member 103a and the cup member 103b, the sealing member 103c is pressed against the plating surface 104a of the substrate 104 (i.e., the active surface of the substrate 104). This forms a sealing structure between the sealing member 103c and the peripheral region of the plating surface 104a of the substrate 104, and at the same time between the plurality of contacts provided in the substrate holder 103 (not shown) and the plating surface 104a of the substrate 104. Form an electrical connection. The sealing structure of the plating surface 104a prevents the plating solution 102 from contacting the above edge of the substrate 104, the edge of the substrate 104 The remainder and the plurality of contacts described above, and thus the contamination of the associated electrolyte from the plating bath 102 (in the plating cycle, only the target portion of the plating surface 104a of the substrate 104 is exposed to the plating solution 102).

In one embodiment, the rotary drive 105 can include a rotatable spindle 105a and a slip ring assembly 105b (which includes a plurality of slip rings). The slip ring assembly 105b is mounted on and electrically isolated from the rotatable mandrel 105a, and the slip ring assembly 105b is electrically interconnected/wired (not shown) and the substrate holder 103 in the rotatable mandrel 105a. Electrical connection. When the rotatable mandrel 105a is rotated, each of the plurality of slip rings of the slip ring assembly 105b can be connected to a corresponding brush (not shown) in an external electronic component (eg, the power supply unit 108 of FIG. 2). An electrical connection is established between the substrate holder 103 and the substrate holder 103. One or more slip rings are typically utilized to provide one or more channels (multiple electron paths insulated from each other). For example, four or six slip rings can be used.

In one embodiment, a motor is used to drive (not shown) the rotatable mandrel 105a. One of the advantages of mounting the tapered member 103a of the substrate holder 103 on the rotatable mandrel 105a is that the substrate holder 103 can be rotated and after being immersed in the plating solution 102 (or before, during immersion). Substrate 104. This can prevent bubble entrapment from appearing on the plating surface 104a of the substrate 104, thereby ensuring uniformity of plating and averaging possible disturbances, and improving the transfer of the electrolyte to the substrate 104. Further, the thickness profile of the plating layer can be easily adjusted by changing the rotational speed of the rotatable mandrel 105a. Different rotational speeds can be used in different operations. When immersing the substrate, the rotational speed is preferably between about 1 and 150 rpm. For a substrate (wafer) having a diameter of 200 mm, the rotation speed is preferably between about 100 and 150 rpm. For a substrate (wafer) having a diameter of 300 mm, the rotation speed is preferably between about 50 and 100 rpm.

Another method of preventing the occurrence of air bubbles remaining on the plating surface 104a of the substrate 104 is an oblique immersion, as shown in FIG. 5 (which is depicted in accordance with the present disclosure). A cross-sectional view of a substrate holder and a rotary actuator of an embodiment is shown. The configuration of FIG. 5 is such that the substrate 104 and the surface 102a of the plating solution 102 form an angle when the substrate 104 is immersed. In particular, oblique immersion can reduce the problem of air bubbles remaining on the plating surface 104a of the substrate 104. Different angles can be used as the electroplating process and the specific details of the substrate holder 103 (eg, clamshell substrate holders) are different. It should be noted that plating at an angle helps prevent the occurrence of air bubbles on the plating surface during the plating process, and when oblique plating is used, the ruthenium in the plated film can also be reduced. In one embodiment, the angle of the plated surface 104a of the substrate 104 relative to the surface 102a of the plating solution 102 is from about 1 to about 5 degrees. In one embodiment, the angle is from about 4 to about 5 degrees. What is more, in the preferred case, the speed at which the substrate 104 is moved into the plating solution 102 is between about 5 and 50 mm/sec. In a more preferred case, the speed at which the substrate 104 is moved into the plating solution 102 is between about 5 and 25 mm/sec. In still more preferred cases, the speed at which substrate 104 is moved into plating solution 102 is between about 8 and 15 millimeters per second. In the best case, the speed at which the substrate 104 is moved into the plating bath 102 is about 12 mm/sec.

Figure 6 is a schematic diagram showing an electroplating apparatus 600 for electrochemically plating a substrate. The electroplating apparatus 600 includes a plating tank 101 (to accommodate the plating solution 102). The plating apparatus 600 includes a substrate holder 103 for holding the substrate 104. The electroplating apparatus 600 further includes a rotary driver 105 and an anode 107, wherein a voltage V is applied to the rotary driver 105 and the anode 107 such that the current I3 flows from the rotary driver 105 to the anode 107.

Figure 7 is a schematic illustration of an electroplating apparatus 700 for electrochemically plating a substrate in accordance with an embodiment of the present disclosure. The electroplating apparatus 700 includes a plating tank 101, a substrate holder 103, a rotary actuator 105, an anode 107, and a current regulating structure 109. Similarly, the plating bath 101 is for accommodating the plating solution 102. The substrate holder 103 can hold the substrate 104 in the plating solution 102. The rotary driver 105 is used to rotate the substrate 104. The current regulating structure 109 is electrically coupled between the rotary driver 105 and the anode 107, wherein the voltage V applied between the current regulating structure 109 and the anode 107 causes the current flowing from the current regulating structure 109 to the anode 107. Current I4. The current I4 will pass from the current modulating structure 109 through the anode 107, the plating solution 102, the substrate 104, the substrate holder 103, the rotary driver 105, and back to the current modulating structure 109. The flow of current I4 in the electrical circuit causes the conductive material in the plating solution 102 to deposit onto the substrate 104.

The function of the current modulating structure 109 is to provide a predetermined impedance value to the electrical circuit. The predetermined impedance is selected such that the variation of the current I4 flowing through the electrical loop is maintained in a small range compared to the current I3 flowing through the electrical loop (where the current variation is in the absence of a current-regulating structure) Measured under conditions of 109). In a preferred case, the predetermined impedance value ranges between 0.02 mΩ and 20 Ω. In a more preferred case, the predetermined impedance value ranges between 0.05 mΩ and 5 Ω. In a still more preferred case, the predetermined impedance value ranges between 0.1 mΩ and 1 Ω. In the best case, the predetermined impedance value is 50 mΩ. It should be noted that the total impedance of the electrical circuit ranges from 1 Ω to 50 Ω.

Figure 8 is a flow chart of a method of electroplating a substrate using an electrochemical method. In operation 801, the substrate is immersed in the plating solution. In operation 802, an anode is provided and electrically coupled to the plating solution (eg, immersed in the plating solution). Operation 803 reveals forming an electrical loop from the beginning of the power supply to the anode, the plating solution, the substrate, and back to the power supply (where a current flows from the power supply to the anode, the plating solution, the substrate, and back to the power supply). In operation 804, a current modulating structure having a predetermined impedance value is provided on the electrical circuit, wherein the predetermined impedance is selected such that the variation of the current flowing through the electrical circuit can be kept within a smaller range, as compared to no The current measurement structure is measured in the case where the current flowing through the electrical circuit causes the conductive material to deposit on the substrate. In a preferred case, the predetermined impedance value ranges between 0.02 mΩ and 20 Ω. In a more preferred case, the predetermined impedance value ranges between 0.05 mΩ and 5 Ω. In a still more preferred case, the predetermined impedance value ranges between 0.1 mΩ and 1 Ω. In the best case, the predetermined impedance value is 50 mΩ. It should be noted that the total impedance of the electrical circuit ranges from 1 Ω to 50 Ω.

In one embodiment, at operation 801 (ie, immersing the substrate to Between the plating solutions, an operation can be performed to form additional layers of conductive metal. First, a barrier layer may be pre-deposited on the surface of the substrate to be electroplated, and the barrier layer preferably comprises tantalum, tantalum nitride (TaN), titanium nitride (TiN) or any suitable material. The barrier layer can typically be deposited on the surface of the substrate to be electroplated using physical vapor deposition (PVD), sputtering or chemical vapor deposition (CVD) processes. The barrier layer prevents copper from diffusing to the semiconductor substrate (because copper reacts with cerium oxide, so the barrier layer must be formed first) and any dielectric layer thereof, thereby increasing reliability. In a preferred embodiment, for a sub-micron sized interconnect structure/member, the barrier layer has a film thickness of between about 25 angstroms and about 500 angstroms. In one embodiment, the barrier layer has a thickness of between about 50 angstroms and about 3,000 angstroms. Thereafter, a PVD copper seed layer can be deposited on the barrier layer. The copper seed layer provides good adhesion to the subsequently plated copper. In one embodiment, the seed layer has a thickness of between about 50 angstroms and about 3,000 angstroms. The seed layer can be patterned for subsequent formation of deposited copper.

Additionally, after electroplating, the plated surface of the substrate can be planarized, such as by chemical mechanical polishing (CMP), to define a conductive interconnect member. The chemical mechanical planarization technique is a process that removes the surface relief of the plated surface of the substrate. The electroplated surface can be planarized using chemical mechanical planarization techniques for subsequent manufacturing processes. In deep submicron IC preparation, chemical mechanical planarization techniques are preferred planarization techniques. For chemical mechanical planarization, the abrasive action is partially mechanical and partially chemical. The mechanical components in the process exert a downward pressure, and the chemical reaction performed increases the rate of material removal, which is typically tailored to the material being processed.

Some embodiments of the present disclosure provide an electroplating apparatus capable of electroplating a substrate, comprising: a plating bath for accommodating a plating solution; and a substrate holder for holding a substrate in the plating solution; The rotary driver is electrically coupled to the substrate holder and is configured to rotate the substrate holder; a power distribution component is electrically coupled to the rotary driver; an anode is disposed in the plating tank, and the anode is immersed in the plating solution; a power supply list The element is electrically coupled between the anode and the power distribution component, thereby forming an electrical circuit; and a current regulating structure for providing a predetermined impedance value to the electrical circuit, wherein the voltage provided by the power supply unit causes a The current flows through the electrical loop, and the predetermined impedance is selected such that the variation of the current flowing through the electrical loop is maintained in a smaller range compared to the current measured without the current modulating member variation.

Some embodiments of the present disclosure provide an electroplating apparatus capable of electroplating a substrate, comprising: a plating bath for accommodating a plating solution; and a substrate holder for holding a substrate in the plating solution; The rotary driver is electrically coupled to the substrate holder and is configured to rotate the substrate holder; an anode is disposed in the plating bath, and the anode is immersed in the plating solution, wherein a voltage applied to the rotary driver and the anode causes a current to be a rotary actuator flows to the anode; and a current-regulating structure electrically coupled to the rotary driver, wherein the predetermined impedance value of one of the current-regulating structures is selected such that the variation of the current is maintained in a smaller range, as compared to The current variation measured under the condition of the current modulating structure.

Some embodiments of the present disclosure provide an electroplating method for electroplating a substrate, comprising: immersing a substrate in a plating solution; electrically coupling an anode to the plating solution; forming an electrical circuit, wherein a current flows from the power supply to the anode, the plating solution, the substrate, and back to the power supply; and a current modulating structure having a predetermined impedance value is provided on the electrical circuit, wherein the predetermined impedance is selected to flow through the electrical The current variation of the current of the loop is maintained in a small range compared to the current variation measured without the current regulating structure, wherein the flow of the current in the electrical loop causes a conductive material to deposit On the substrate.

The methods and features of the present disclosure have been fully disclosed in the foregoing embodiments and description. It is to be understood that any modifications or changes may be made without departing from the spirit of the disclosure, and are still covered by the scope of the disclosure.

In addition, the scope of the present application should not be limited to the specific embodiments of the processes, machines, articles of manufacture, compositions, means, methods and steps of the invention. Those skilled in the art of the present invention can easily infer the various processes, machines, articles of manufacture, materials, means, methods and steps that have been developed or developed in the future. The embodiments described herein have substantially the same function or substantially the same result, and the present disclosure may be utilized. Therefore, the scope of the patent application is intended to cover, for example, the above-described processes, machines, articles of manufacture, compositions of matter, means, methods and procedures. In addition, each request item constitutes a separate embodiment, and combinations between different request items and implementations are also within the scope of the disclosure.

200‧‧‧Electroplating equipment

101‧‧‧ plating bath

102‧‧‧ plating solution

103‧‧‧Substrate holder

104‧‧‧Substrate

105‧‧‧Rotary drive

106‧‧‧Power distribution components

107‧‧‧Anode

108‧‧‧Power supply unit

109‧‧‧current adjustment structure

I2‧‧‧ current

V‧‧‧ voltage

Claims (10)

An electroplating apparatus for electrochemically plating a substrate, comprising: a plating bath for accommodating a plating solution; a substrate holder for holding one of the substrates in the plating solution; and a rotary driver, and The substrate holder is electrically coupled to rotate the substrate holder; a power distribution component is electrically coupled to the rotary driver; an anode is disposed in the plating tank, and the anode is immersed in the plating solution a power supply unit electrically coupled between the anode and the power distribution component to form an electrical circuit; and a current regulating structure for providing a predetermined impedance value to the electrical circuit, wherein The voltage supplied by the power supply unit causes a current to flow through the electrical loop, and the predetermined impedance is selected such that the variation of the current flowing through the electrical loop is maintained in a smaller range, as compared to no The current variation measured under the condition of the current modulating structure. The electroplating apparatus of claim 1, wherein the anode is made of gold, zinc, nickel, silver, copper or nickel. The electroplating apparatus of claim 1, wherein the rotary actuator comprises a rotatable spindle and a slip ring assembly. The electroplating apparatus of claim 1, wherein the power supply unit comprises a DC power supply unit. The electroplating apparatus of claim 1, wherein the current modulating structure is disposed on the electrical circuit and is not located in the plating bath. The electroplating apparatus of claim 1, wherein the predetermined impedance value ranges between about 0.02 mΩ and about 20 Ω. The electroplating apparatus of claim 1, wherein the predetermined impedance value ranges between about 0.05 mΩ to about 5 Ω. The electroplating apparatus of claim 1, wherein the predetermined impedance value ranges between about 0.1 mΩ to about 1 Ω. An electroplating apparatus for electrochemically plating a substrate, comprising: a plating bath for accommodating a plating solution; a substrate holder for holding one of the substrates in the plating solution; and a rotary driver, and The substrate holder is electrically coupled to rotate the substrate holder; an anode is disposed in the plating tank, and the anode is immersed in the plating solution, wherein a voltage applied to the rotating driver and the anode is Causing a current to flow from the rotary driver to the anode; and a current modulating member electrically coupled to the rotary driver, wherein a predetermined impedance value of the current modulating member is selected such that the variation of the current is maintained In the small range, the current variation measured compared to the condition without the current-regulating structure. An electroplating method for electroplating a substrate, comprising: Immersing a substrate in a plating solution; electrically coupling an anode to the plating solution; forming an electrical circuit, wherein a current flows in the electrical circuit from a power supply to the anode, the plating solution And returning the substrate to the power supply; and providing a current modulation structure having a predetermined impedance value on the electrical circuit, wherein the predetermined impedance is selected such that a variation of the current flowing through the electrical circuit is maintained In a smaller range, the flow measured in the electrical circuit causes a conductive material to deposit on the substrate compared to the variation measured without the current modulating structure.