Method and device for manufacturing semiconductor structure

Abstract

The present invention discloses a method and apparatus for fabricating a semiconductor structure, belonging to the field of semiconductor fabrication. The fabrication method comprises at least: providing a substrate comprising at least one silicon conductive region; forming a metal layer on the substrate; performing a first annealing process, wherein the metal layer reacts with the silicon conductive region on the substrate to form a first metal silicide; placing the substrate in an etching reaction tank and removing the unreacted metal layer; during the removal of the metal layer, the etching solution in the etching reaction tank sequentially passes through a dissolution tank and an adsorption tank and returns to the etching reaction tank; removing the substrate and performing a second annealing process on the first metal silicide to form a second metal silicide. The method and apparatus for fabricating a semiconductor structure provided by the present invention can accelerate fabrication and improve the performance of semiconductor structures.

Description

Technical Field

[0001] The present invention belongs to the field of semiconductor manufacturing, and in particular relates to a method and device for manufacturing a semiconductor structure. Background Art

[0002] With the continuous development of semiconductor technology, the size of semiconductor devices continues to shrink, which constantly poses new challenges to the manufacturing process of devices. In the manufacture of semiconductor devices, self-aligned silicide is a key process in semiconductors. This process deposits a layer of metal on the exposed silicon surface of the source, drain and polysilicon gate. After a rapid thermal annealing reaction to generate metal silicide, the unreacted metal layer is removed by a wet etching process. But if Figure 1 As shown in the figure, in the process of removing the metal layer, due to the low reactivity of some metals, it is difficult to dissolve in commonly used etching agents such as high-temperature sulfuric acid and hydrogen peroxide. The metal particles that are not completely dissolved are scattered and fall into the etching solution tank and are re-adhered to the surface of the wafer, resulting in the unreacted metal not being completely removed. Prolonging the reaction time for too long may cause damage to the metal silicide and affect the quality of the metal silicide.

[0003] By adding a microwave device to the wet etching tank for removing the metal layer, the dissolution rate of metal particles can be accelerated. However, the microwave device will cause large temperature fluctuations in the etching solution, affecting the metal silicide or other film layers of the semiconductor device, and reducing the yield and performance of the semiconductor device. Summary of the Invention

[0004] The purpose of the present invention is to provide a method and device for manufacturing a semiconductor structure. The method and device for manufacturing a semiconductor structure provided by the present invention can ensure that the metal layer is completely removed, prevent over-etching, speed up the manufacturing speed, improve the manufacturing quality, and obtain high-quality metal silicide.

[0005] To solve the above technical problems, the present invention provides a method for manufacturing a semiconductor structure, which at least comprises:

[0006] Providing a substrate, wherein the substrate comprises at least one silicon conductive region;

[0007] forming a metal layer on the substrate;

[0008] Through the first annealing, the metal layer and the silicon conductive region on the substrate react to form a first metal silicide;

[0009] placing the substrate into an etching reaction tank to remove the unreacted metal layer, wherein during the removal of the metal layer, the etching solution in the etching reaction tank sequentially passes through a dissolving tank and an adsorption tank and returns to the etching reaction tank;

[0010] The substrate is removed, and the first metal silicide is subjected to a second annealing to form a second metal silicide.

[0011] In one embodiment of the present invention, the metal layer is at least one of metal nickel, metal cobalt, nickel-platinum alloy or nickel-cobalt alloy.

[0012] In one embodiment of the present invention, the etching solution is a mixed solution of hydrochloric acid, sulfuric acid and hydrogen peroxide. In the etching solution, the volume fraction of hydrochloric acid is 0.01%~20%, the volume fraction of sulfuric acid is 50%~90%, and the volume fraction of hydrogen peroxide is 10%~50%.

[0013] In one embodiment of the present invention, when removing the metal layer, the temperature of the etching solution in the etching reaction tank is 120° C. to 220° C.

[0014] In one embodiment of the present invention, when the etching liquid enters the dissolving tank, an ultrasonic generator and a stirrer are provided in the dissolving tank to perform ultrasonic stirring treatment on the etching liquid.

[0015] In one embodiment of the present invention, the adsorption tank includes an adsorption membrane, and after the etching solution passes through the adsorption tank, part of the metal ions in the etching solution are removed.

[0016] In one embodiment of the present invention, a first detection unit is provided at the output end of the etching reaction tank, and the first detection unit monitors the number of metal particles in the etching solution in real time, and monitors and records the maximum number of metal particles per unit time as X. m When the first detection unit detects that the number of the metal particles in the etching solution is less than 1%X m When the etching reaches 0.05 μs / s, stop etching.

[0017] The present invention also provides a device for manufacturing a semiconductor structure, comprising:

[0018] Etching reaction tank;

[0019] a dissolution tank, arranged at the output end of the etching reaction tank;

[0020] an adsorption tank, disposed at an output end of the dissolution tank, the output end of the adsorption tank being connected to the etching reaction tank; and

[0021] The connecting pipeline connects the etching reaction tank, the dissolution tank and the adsorption tank.

[0022] In one embodiment of the present invention, a first detection unit is provided on the connecting pipeline between the etching reaction tank and the dissolution tank.

[0023] In one embodiment of the present invention, a loop is provided between the output end and the input end of the dissolution tank, and a second detection unit is provided on the loop for detecting the amount of impurities in the etching solution after passing through the dissolution tank.

[0024] In summary, the present invention provides a method and device for manufacturing a semiconductor structure. The unexpected technical effect of this application is that the unreacted metal layer can be completely removed when forming a metal silicide, and the metal particles in the etching reaction tank can be reduced, the damage to the metal silicide can be reduced, and the quality of the formed metal silicide can be improved. It can reduce the influence of impurities in the etching solution on etching, and accelerate the reaction speed, improve the etching speed and effect, and can purify the etching solution and reuse it, improve the utilization efficiency of the etching solution, and reduce production costs. It can ensure that the metal layer is completely removed, and accurately control the etching time to prevent over-etching and save etching time. Through the manufacturing method provided by this application, the manufacturing speed can be accelerated, the manufacturing quality can be improved, and high-quality metal silicide can be obtained, thereby improving the stability of semiconductor devices.

[0025] Of course, any product implementing the present invention does not necessarily need to achieve all of the advantages described above at the same time. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings required for describing the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0027] Figure 1 This is a scanning electron microscope image of metal silicide after the metal layer is removed in the prior art.

[0028] Figure 2 FIG. 1 is a schematic diagram of an apparatus for fabricating a semiconductor structure according to an embodiment.

[0029] Figure 3 The figure is a flow chart of manufacturing a semiconductor structure according to an embodiment.

[0030] Description of labels:

[0031] 10. Substrate; 11. Metal layer; 12. First metal silicide; 13. Second metal silicide; 100. Etching reaction tank; 101. Etching solution; 102. Metal particles; 103. First detection unit; 200. Dissolution tank; 201. Ultrasonic generator; 202. Agitator; 203. Second detection unit; 300. Adsorption tank; 301. Adsorption film; 400. Connecting pipeline. DETAILED DESCRIPTION

[0032] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making any creative efforts shall fall within the scope of protection of the present invention.

[0033] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art to which this application pertains. The terms used herein in the specification of this application are only for the purpose of describing specific embodiments and are not intended to limit this application.

[0034] In the description of this specification, it should be understood that the directions or positional relationships indicated by terms such as "center," "upper," "lower," "front," "back," "left," and "right" are based on the directions or positional relationships shown in the accompanying drawings and are intended solely to facilitate the description of this solution and simplify the description. They do not indicate or imply that the devices or components referred to must have a specific direction, be constructed, or operate in a specific direction. Therefore, they should not be construed as limitations on this solution. Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0035] The present invention provides a method and apparatus for manufacturing a semiconductor structure. In the process of forming a metal silicide, by setting an etching reaction tank, a dissolution tank and an adsorption tank, the unreacted metal layer can be quickly removed, and the metal particles in the etching reaction tank can be reduced, thereby accelerating the reaction speed, reducing damage to the metal silicide, and improving the quality of the formed metal silicide, thereby improving the performance of semiconductor devices including the metal silicide.

[0036] See also Figure 2As shown, in one embodiment of the present invention, a device for manufacturing a semiconductor structure is provided, which can be used in a wet etching process for manufacturing semiconductor devices. In this embodiment, for example, the device for manufacturing metal silicide is used for explanation. The device includes at least an etching reaction tank 100, a dissolution tank 200, an adsorption tank 300, a connecting pipe 400, and multiple detection units. The connecting pipe 400 connects the etching reaction tank 100, the dissolution tank 200, and the adsorption tank 300 to form a loop of etching reaction tank-dissolution tank-adsorption tank-etching reaction tank. The detection unit includes a first detection unit 103 and a second detection unit 203 to detect the number of metal particles in the etching solution and determine the etching progress. The first detection unit 103 is arranged on the connecting pipe 400 between the etching reaction tank 100 and the dissolution tank 200, and the second detection unit 203 is arranged at the output end of the dissolution tank 200 to determine the dissolution status of the metal particles in the dissolution tank 200. The device of the present application can prevent metal particles from aggregating in the etching reaction tank 100 , thereby improving the quality of the formed metal silicide.

[0037] See also Figure 2 As shown, in one embodiment of the present invention, a substrate 10 and an etching solution 101 are placed in an etching reaction tank 100. Multiple substrates 10 are placed in a cleaning basket (not shown), which is then placed in the etching reaction tank 100. The etching solution 101 completely covers the substrates 10, and multiple substrates 10 are etched simultaneously to improve etching efficiency. A heater (not shown) is also provided in the etching reaction tank 100 to heat the etching solution 101 during the etching process and control the temperature of the etching solution to increase the etching rate. In this embodiment, during the process of forming metal silicide, when removing the unreacted metal layer, some of the metal layer remains undissolved and falls off in the form of metal particles 102.

[0038] See also Figure 2 As shown, in one embodiment of the present invention, a dissolution tank 200 is disposed at the output end of the etching reaction tank 100, and the dissolution tank 200 and the etching reaction tank 100 are connected by a connecting pipe 400. An ultrasonic generator 201 and an agitator 202 are also disposed within the dissolution tank 200. In this embodiment, the ultrasonic generator 201 is disposed, for example, outside the dissolution tank 200 to ultrasonically influence the etching solution within the dissolution tank 200, and the agitator 202 is disposed within the dissolution tank 200 to agitate the etching solution within the dissolution tank 200. When the etching solution 101 containing metal particles 102 enters the dissolution tank 200, the agitation and ultrasonic action can accelerate the dissolution of the metal particles 102, causing the metal particles 102 within the etching solution 101 to dissolve rapidly, thereby increasing the etching speed. The present invention does not limit the rotation speed of the agitator and the power of the ultrasonic generator, and the specific settings are based on the type of etching solution selected in the process and the substances in the etching solution.

[0039] See also Figure 2 As shown, in one embodiment of the present invention, an adsorption tank 300 is disposed at the output end of the etching and dissolution tank 200. The dissolution tank 200 and the adsorption tank 300 are connected via a connecting pipe 400, and the dissolved etching solution 101 is transported to the adsorption tank 300. The adsorption tank 300 is also provided with an adsorption membrane 301 to adsorb impurities in the etching solution 101. Multiple layers of adsorption membrane 301 are disposed between the inlet and outlet of the adsorption tank 300 to enhance the adsorption effect. In this embodiment, the adsorption membrane 301 is, for example, an ion exchange resin membrane, which adsorbs metal ions in the etching solution 101 to purify the etching solution 101. The output end of the adsorption tank 300 is connected to the etching reaction tank 100, and the dissolved and adsorbed etching solution 101 is added to the etching reaction tank 100. On the one hand, it can reduce the impact of impurities in the etching solution 101 on substrate etching, reduce the concentration of impurities, speed up the reaction, and improve the etching speed and effect. On the other hand, the etching solution 101 can be purified and reused, thereby improving the utilization efficiency of the etching solution and reducing production costs.

[0040] See also Figure 2 As shown, in one embodiment of the present invention, a first detection unit 103 is disposed on the connecting pipe 400 between the etching reaction tank 100 and the dissolution tank 200. It is used to detect the amount of impurities in the etching solution 101 delivered from the etching reaction tank 100. In this embodiment, for example, the detection unit 103 detects the amount of metal particles 102 in the etching solution 101 to determine the progress of etching and to stop the etching process. A loop is provided between the output and input ends of the dissolution tank 200. A second detection unit 203 is disposed on the loop to detect the amount of impurities in the etching solution 101 after it has passed through the dissolution tank 200. In this embodiment, for example, the detection unit 203 detects whether metal particles 102 are still present in the etching solution 101. If metal particles 102 are still present, the etching solution 101 is re-entered into the dissolution tank 200 through the loop for dissolution until the second detection unit 203 detects no more metal particles. In this embodiment, multiple valves (not shown) are also provided on the connecting pipe 400 to control the flow of the etching solution, which will not be further explained here. In one embodiment of the present application, the first detection unit 103 and the second detection unit 203 include, for example, a light-obstruction particle counter.

[0041] See also Figures 2 to 3As shown, in one embodiment of the present invention, a method for manufacturing a semiconductor structure is provided, including: providing a substrate 10, the substrate 10 including at least one silicon conductive region, forming a metal layer 11 on the substrate 10, and reacting the metal layer 11 with the silicon conductive region on the substrate 10 through a first annealing to form a first metal silicide 12. The substrate 10 is placed in an etching reaction tank 100, and the unreacted metal layer 11 is removed. During the process of removing the metal layer 11, the etching solution 101 in the etching reaction tank 100 passes through a dissolution tank 200 and an adsorption tank 300 in sequence, and returns to the etching reaction tank 100. The substrate 10 is removed, and the first metal silicide 12 is subjected to a second annealing to form a second metal silicide 13. The manufacturing method provided by the present application can accelerate the manufacturing speed, improve the manufacturing quality, and obtain high-quality metal silicide.

[0042] See also Figures 2 to 3 As shown, in one embodiment of the present invention, substrate 10 may be any material suitable for forming a semiconductor structure, such as silicon carbide (SiC), gallium nitride (GaN), aluminum nitride (AlN), indium nitride (InN), indium phosphide (InP), gallium arsenide (GaAs), silicon germanium (GeSi), sapphire, silicon wafers, or other semiconductor materials formed from III / V compounds, including stacked structures composed of these semiconductor materials, or silicon-on-insulator (SOI), stacked silicon-on-insulator (SiOI), silicon germanium-on-insulator (SiGeOI), and germanium-on-insulator (GeOI). The material of substrate 10 may be selected, for example, based on the type of semiconductor device to be subsequently formed, and the present invention does not limit the specific material of substrate 10. Substrate 10 includes at least one silicon conductive region, where the silicon conductive region may be, for example, a region of substrate 10 on a silicon substrate, or a polysilicon gate, which is not specifically limited in this application. That is, the semiconductor device is fabricated before depositing the metal layer 11, i.e., the metal silicide is fabricated before fabricating the metal wiring layer. In this embodiment, the fabrication process is described in detail using a silicon substrate as an example.

[0043] See also Figures 2 to 3 As shown, in one embodiment of the present invention, a metal layer 11 is deposited on a substrate 10. Metal layer 11 is at least one of nickel, cobalt, a nickel-platinum alloy, or a nickel-cobalt alloy, and is, for example, a nickel-platinum alloy, with a platinum mass fraction of, for example, 5% to 10%, to increase the thermal stability of metal layer 11 and reduce the generation of defects. In this embodiment, metal layer 11 is obtained, for example, by physical vapor deposition (PVD), and has a thickness of, for example, 20 nm to 30 nm, providing a sufficient nickel source for the formation of self-aligned metal silicide.

[0044] See also Figures 2 to 3As shown, in one embodiment of the present invention, after the metal layer 11 is formed, the substrate 10 is subjected to a first annealing, wherein the preset temperature of the first annealing is, for example, 200°C to 270°C, and the annealing time is, for example, 20s to 5min. After the annealing is completed, the substrate 10 is cooled until it cools to room temperature. By controlling the conditions of the first annealing, the nickel metal in the metal layer 11 reacts with the substrate to form a first metal silicide 12. In this embodiment, the first metal silicide 12 is, for example, a first nickel-based silicide Ni2Si, and the resistance of the first nickel-based silicide Ni2Si is relatively large, and the thickness is, for example, 10nm to 15nm. Since the thickness of the metal layer 11 is relatively large, it can provide a sufficient nickel source, and there will not be excessive heat energy in the first annealing process, thereby reducing the probability of defects.

[0045] See also Figures 2 to 3 As shown, in one embodiment of the present invention, after forming the first metal silicide 12, the substrate 10 is placed in an etching reaction tank 100 to remove the unreacted metal layer 11. The etching solution 101 in the etching reaction tank 100 is, for example, a mixed solution of hydrochloric acid, sulfuric acid, and hydrogen peroxide. The mass fraction of the hydrochloric acid used is, for example, 36% to 38%, the mass fraction of the sulfuric acid is, for example, 92.5% to 98%, and the mass fraction of the hydrogen peroxide is, for example, 25% to 30%. In the etching solution 101, the volume fraction of hydrochloric acid is, for example, 0.01% to 20%, the volume fraction of sulfuric acid is, for example, 50% to 90%, and the volume fraction of hydrogen peroxide is, for example, 10% to 50%. During the removal of the metal layer 11, nickel reacts with the etching solution, but platinum reacts more slowly with the etching solution, falling off in the form of particles and remaining in the etching solution. By adding hydrochloric acid to the etching solution, a complex is formed between platinum and chloride ions in the dissolution tank 200 , which can remove at least part of the metal ions, such as platinum ions, in the etching solution 101 in the adsorption tank 300 , thereby purifying the etching solution.

[0046] See also Figures 2 to 3 As shown, in one embodiment of the present invention, when removing the metal layer 11, the temperature of the etching solution 101 is heated to 120°C to 220°C by a heater in the etching reaction tank 100. That is, under the chemical reaction of the etching solution 101, part of the metal layer 11 is dissolved into ions, and part of the metal layer 11 is peeled off in the form of metal particles 102, thereby quickly removing the metal layer 11 and reducing damage to the first metal silicide 12 caused by excessive etching time.

[0047] See also Figures 2 to 3 As shown, in one embodiment of the present invention, during the etching process, the etching solution 101 with metal particles 102 in the etching reaction tank 100 enters the dissolution tank 200 through the connecting pipe 400, and the first detection unit 103 monitors the number of metal particles 102 in the etching solution 101 in real time, and monitors and records the maximum number of metal particles 102 per unit time as X.m For example, the maximum number of metal particles 102 per second is X m The etching solution containing metal particles 102 enters the dissolution tank 200. The ultrasonic power of the ultrasonic generator 201 in the dissolution tank 200 is, for example, 50W to 5000W, and the stirring rate of the stirrer 202 is, for example, 200 rpm / min to 20,000 rpm / min. Under the action of ultrasound and stirring, mechanical shear force and microwave energy accelerate the dissolution of the metal particles 102 in the etching solution 101. In the loop outside the dissolution tank 200, the second detection unit 203 detects the number of metal particles 102 in the etching solution 101 after passing through the dissolution tank 200. If metal particles 102 are still present, the etching solution 101 in the loop re-enters the dissolution tank 200 to dissolve until the second detection unit 203 detects no more metal particles 102. The platinum in the metal particles 102 dissolves in the etching solution 101, forming an ion complex. By providing a dissolution tank, the dissolution of the metal particles can be accelerated, and the metal particles can be prevented from aggregating in the etching reaction tank, thereby preventing the metal particles from adhering to the first metal silicide and reducing defects.

[0048] See also Figures 2 to 3 As shown, in one embodiment of the present invention, when the second detection unit 203 fails to detect the metal particles 102, the etching solution 101 in the dissolution tank 200 enters the adsorption tank 300 through the connecting pipe 400. At least two adsorption membranes 301 are provided between the inlet and outlet of the dissolution tank 200. After the etching solution containing platinum metal ions passes through the adsorption membranes 301, the adsorption membranes 301 adsorb the platinum metal ions, thereby purifying the etching solution. During adsorption, the following reaction occurs:

[0049] 2RCl+PtCl6 2- =R2PtCl6+2Cl - ;

[0050] Here, R represents the organic matter in the adsorption film 301. The adsorption film 301 can adsorb the platinum metal ions in the etching solution, thereby purifying the etching solution 101. The purified etching solution 101 can be reused, improving the utilization efficiency of the etching solution and reducing production costs. At the same time, it reduces the concentration of impurities, accelerates the reaction, and improves the etching speed and effect.

[0051] See also Figures 2 to 3 As shown, in one embodiment of the present invention, the purified etching solution 101 enters the etching reaction tank 100 through the connecting pipe 400 to continue metal etching. Among them, etching, dissolution and adsorption are carried out simultaneously. When the first detection unit 103 detects in real time that the number of metal particles 102 in the etching solution 101 is less than 1%X mWhen the number of metal particles reaches 0.5, the etching is considered complete, and the substrate 10 is removed and cleaned, for example, with anhydrous ethanol, isopropyl alcohol, or deionized water. Judging whether the etching is complete by the number of metal particles can ensure that the metal layer is completely removed. At the same time, the etching time can be accurately controlled to prevent over-etching and save etching time.

[0052] See also Figures 2 to 3 As shown, in one embodiment of the present invention, after removing the unreacted metal layer 11, the first metal silicide 12 is subjected to a second annealing to convert the high-resistance first metal silicide 12 formed by the first annealing into a low-resistance second metal silicide 13. The second annealing may be performed, for example, by laser annealing or spike annealing, and the substrate 10 is instantaneously heated to 600°C to 1000°C under the action of the laser, with the annealing time being, for example, 0.1ms to 2ms. That is, the substrate 10 is subjected to rapid high-temperature annealing to form the second metal silicide 13. In this embodiment, the second metal silicide is, for example, a second nickel-based silicide, NiSi, and the second nickel-based silicide has a low resistance, thereby forming a low-resistance second metal silicide 13. The thickness of the second metal silicide 13 is, for example, 10nm to 15nm. By improving the fabrication method and apparatus, high-quality self-aligned metal silicide can be obtained, avoiding self-aligned metal silicide defects caused by incomplete metal layer removal or metal particles, thereby improving the quality of the self-aligned metal silicide. This also reduces the contact resistance between the later-formed conductive plug and the gate or source / drain, improving device performance and thus enhancing the stability of the semiconductor device. Furthermore, the self-aligned metal silicide can serve as a contact structure for the semiconductor device, leading out the source, drain, and gate.

[0053] In summary, the present invention provides a method and device for manufacturing a semiconductor structure. By improving the manufacturing device and manufacturing method, the unexpected technical effect of this application is that the unreacted metal layer can be completely removed when forming the metal silicide, and the metal particles in the etching reaction tank can be reduced, the damage to the metal silicide can be reduced, and the quality of the formed metal silicide can be improved. It can reduce the influence of impurities in the etching solution on the etching, and accelerate the reaction speed, improve the etching speed and effect, and can purify the etching solution and reuse it, improve the utilization efficiency of the etching solution, and reduce production costs. It can ensure that the metal layer is completely removed, and accurately control the etching time to prevent over-etching and save etching time. Through the manufacturing method provided by this application, the manufacturing speed can be accelerated, the manufacturing quality can be improved, and high-quality metal silicide can be obtained, thereby improving the stability of semiconductor devices.

[0054] The above description of the illustrated embodiments of the present invention (including that described in the Abstract) is not intended to be exhaustive or to limit the invention to the precise forms disclosed herein. Although specific embodiments of the present invention and examples of the present invention are described herein for illustrative purposes only, as those skilled in the art will recognize and appreciate, various equivalent modifications are possible within the spirit and scope of the present invention. As noted, modifications may be made to the present invention in light of the above description of the illustrated embodiments of the present invention, and such modifications will be within the spirit and scope of the present invention.

[0055] The above description is only a preferred embodiment of the present application and an explanation of the technical principles used. Those skilled in the art should understand that the scope of the invention involved in this application is not limited to the technical solutions formed by the specific combination of the above technical features, but should also cover other technical solutions formed by any combination of the above technical features or their equivalent features without departing from the inventive concept, such as the technical solutions formed by replacing the above features with (but not limited to) technical features with similar functions disclosed in this application. In addition to the technical features described in the specification, the remaining technical features are known technologies to those skilled in the art. In order to highlight the innovative features of the present invention, the remaining technical features will not be repeated here.

Claims

1. A method for manufacturing a semiconductor structure, characterized in that: At least: Providing a substrate, wherein the substrate comprises at least one silicon conductive region; forming a metal layer on the substrate; Through the first annealing, the metal layer and the silicon conductive region on the substrate react to form a first metal silicide; The substrate is placed in an etching reaction tank to remove the unreacted metal layer. When removing the metal layer, the etching solution in the etching reaction tank passes through the dissolution tank and the adsorption tank in sequence and returns to the etching reaction tank. The output end of the etching reaction tank is provided with a first detection unit, which monitors the number of metal particles in the etching solution in real time, and monitors and records the maximum number of metal particles per unit time as X. m When the first detection unit detects that the number of the metal particles in the etching solution is less than 1%X m When the etching temperature reaches 0.05 t / s, the etching is stopped; a loop is set between the output end and the input end of the dissolving tank, and a second detection unit is set on the loop to detect the amount of impurities in the etching solution after passing through the dissolving tank; The substrate is removed, and the first metal silicide is subjected to a second annealing to form a second metal silicide.

2. The method for manufacturing a semiconductor structure according to claim 1, wherein: The metal layer is at least one of metal nickel, metal cobalt, nickel-platinum alloy or nickel-cobalt alloy.

3. The method for manufacturing a semiconductor structure according to claim 1, wherein: The etching solution is a mixed solution of hydrochloric acid, sulfuric acid and hydrogen peroxide. In the etching solution, the volume fraction of hydrochloric acid is 0.01% to 20%, the volume fraction of sulfuric acid is 50% to 90%, and the volume fraction of hydrogen peroxide is 10% to 50%.

4. The method for manufacturing a semiconductor structure according to claim 1, wherein: When removing the metal layer, the temperature of the etching solution in the etching reaction tank is 120° C. to 220° C.

5. The method for manufacturing a semiconductor structure according to claim 1, wherein: When the etching liquid enters the dissolving tank, an ultrasonic generator and a stirrer are provided in the dissolving tank to perform ultrasonic stirring treatment on the etching liquid.

6. The method for manufacturing a semiconductor structure according to claim 1, wherein: The adsorption tank includes an adsorption membrane, and after the etching solution passes through the adsorption tank, part of the metal ions in the etching solution are removed.

7. A device for manufacturing a semiconductor structure, used in the method for manufacturing a semiconductor structure according to any one of claims 1 to 6, characterized in that: include: Etching reaction tank; a dissolution tank, arranged at the output end of the etching reaction tank; An adsorption tank is provided at the output end of the dissolution tank, and the output end of the adsorption tank is connected to the etching reaction tank; as well as A connecting pipeline connects the etching reaction tank, the dissolution tank and the adsorption tank; A first detection unit is provided on the connecting pipeline between the etching reaction tank and the dissolution tank; A loop is provided between the output end and the input end of the dissolving tank, and a second detection unit is provided on the loop for detecting the amount of impurities in the etching solution after passing through the dissolving tank.

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