A wet etching system

Abstract

The utility model discloses a kind of wet etching systems, belong to semiconductor technical field, the wet etching system at least includes: multiple etching chambers, each output waste liquid;Heat exchange equipment, with multiple the etching chamber is connected, the waste liquid is mixed and reacts in the heat exchange equipment;And reactor, with the heat exchange equipment is connected.The wet etching system provided by the utility model can reduce the harm and pollution of etching system to environment, and also can recover the heat in etching system, improve energy utilization.

Description

Technical Field

[0001] This invention belongs to the field of semiconductor technology, and specifically relates to a wet etching system. Background Technology

[0002] In integrated circuit manufacturing, there are hundreds of process steps, making the process complex and requiring high precision. Among them, wet etching, as a necessary process in the back-end fabrication stage, can reduce chip package size, lower package mounting height, and improve chip thermal diffusion efficiency, mechanical properties, and electrical properties. However, wet etching systems typically use highly polluting chemicals, which, if not handled properly, can cause significant environmental pollution and harm. Utility Model Content

[0003] The purpose of this invention is to provide a wet etching system that can reduce the pollution and harm of wet etching to the environment, and can also recover heat from the wet etching system to improve energy utilization.

[0004] To solve the above-mentioned technical problems, this utility model is achieved through the following technical solution:

[0005] This utility model provides a wet etching system, comprising at least:

[0006] Multiple etching chambers, each discharging waste liquid;

[0007] A heat exchange device, connected to a plurality of the etching chambers, wherein the waste liquid is mixed and reacted within the heat exchange device; and

[0008] The reactor is connected to the heat exchange equipment.

[0009] In one embodiment of the present invention, the acidity or alkalinity of the waste liquid output from at least one of the etching chambers is different from that of the waste liquid output from the other etching chambers.

[0010] In one embodiment of this utility model, the waste liquid output from multiple etching chambers simultaneously arrives at the heat exchange device.

[0011] In one embodiment of the present invention, the heat exchange device includes a cavity, in which the waste liquid is mixed and reacted.

[0012] In one embodiment of the present invention, the heat exchange device further includes a heat exchange pipe, which is disposed within the cavity.

[0013] In one embodiment of this utility model, the heat exchange pipe is a straight pipe, a U-shaped pipe, a spiral coil, or a serpentine pipe.

[0014] In one embodiment of the present invention, the cavity includes a top and a bottom disposed opposite to each other, and the reactor is connected to the heat exchange device through the top.

[0015] In one embodiment of the present invention, the wet etching system further includes a liquid discharge pipe, which is connected to the heat exchange device through the bottom.

[0016] In one embodiment of this invention, a catalyst is provided inside the reactor.

[0017] In one embodiment of this utility model, the heat exchange device is a type of indirect heat exchanger, which includes a shell-and-tube heat exchanger, a coiled tube heat exchanger, a wound tube heat exchanger, a plate heat exchanger, a jacketed heat exchanger, a spray heat exchanger, and a shell-and-tube heat exchanger.

[0018] In summary, this utility model provides a wet etching system. Through improvements to the wet etching system, the unexpected technical effect of this application is the ability to avoid the discharge of highly hazardous waste acid or alkali, allowing the wet etching system to emit harmless gases and low-hazard neutral waste liquid, thereby reducing the environmental pollution and harm caused by the wet etching system. Furthermore, the wet etching system provided by this utility model can recover heat from the etching system, avoiding heat waste and improving energy utilization efficiency. Attached Figure Description

[0019] To more clearly illustrate the technical solutions of the embodiments of this utility model, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0020] Figure 1 This is a schematic diagram of a wet etching system in one embodiment.

[0021] Figure 2 This is a diagram illustrating the steps of processing a wafer in an etching chamber according to one embodiment.

[0022] Label Explanation:

[0023] 101, First chamber; 1011, First waste liquid; 102, Second chamber; 1021, Second waste liquid; 20, Heat exchange equipment; 201, Chamber; 2011, Top; 2012, Bottom; 202, Heat exchange pipe; 2021, Heat exchange medium; 30, Reactor; 301, Catalyst; 40, Liquid discharge pipe. Detailed Implementation

[0024] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of the present utility model.

[0025] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. The terminology used herein in the specification of this application is for the purpose of describing particular embodiments only and is not intended to be limiting of this application.

[0026] In the description of this specification, it should be understood that the terms "center," "upper," "lower," "front," "rear," "left," and "right," etc., indicating orientation or positional relationships, are based on the orientation or positional relationships shown in the accompanying drawings and are only for the convenience of describing this solution and simplifying the description, and do not indicate or imply that the device or component referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation 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.

[0027] Please see Figure 1 As shown, this utility model provides a wet etching system, including, for example, multiple etching chambers, a heat exchange device 20, and a reactor 30. Each of the multiple etching chambers is connected to the heat exchange device 20, which includes, for example, a cavity 201 and heat exchange pipes 202, with the heat exchange pipes 202 disposed within the cavity 201. The reactor 30 is connected to the heat exchange device 20. In the wet etching system provided by this utility model, each of the multiple etching chambers outputs waste liquid to the heat exchange device 20. The waste liquid mixes and reacts within the cavity 201 to generate a mixed gas. This mixed gas then enters the reactor 30 for further reaction, achieving harmless treatment of the waste gas. The wet etching system provided by this utility model, through the heat exchange device 20 and the reactor 30, can harmlessly treat the waste liquid output from the etching chambers and the mixed gas output from the heat exchange device 20, reducing the environmental harm and pollution caused by the wet etching system. Furthermore, the wet etching system provided by this invention can recover the heat released by the waste liquid due to the reaction through the heat exchange pipe 202, avoiding heat waste and improving energy utilization. The wet etching system provided by this invention can be used in various wet etching processes. For example, the technical solution will be described in detail using the silicon wafer wet thinning process as an example.

[0028] Please see Figure 1As shown, in one embodiment of this invention, the etching chamber provides space for wet etching of the wafer. Specifically, the etching solution performs wet etching on the wafer in the etching chamber, and waste liquid is output after etching is completed. There may be multiple etching chambers, for example, and the acidity or alkalinity of the waste liquid output from at least one etching chamber differs from that of the waste liquids output from the other etching chambers. In this embodiment, there are, for example, two etching chambers, including a first chamber 101 and a second chamber 102. The chemical solution in the first chamber 101 is, for example, an acidic chemical solution. After the acidic chemical solution etches the wafer in the first chamber 101, the first chamber 101 outputs a first waste liquid 1011, and the pH of the first waste liquid 1011 is, for example, less than 7. The chemical solution in the second chamber 102 is, for example, an alkaline chemical solution. After the alkaline chemical solution etches the wafer in the second chamber 102, the second chamber 102 outputs a second waste liquid 1021, and the pH of the second waste liquid 1021 is greater than 7. The first waste liquid 1011 and the second waste liquid 1021 are highly toxic, so they must be treated before being discharged to reduce their harm to the environment.

[0029] Please see Figure 1 As shown, in one embodiment of this invention, the acidic solution in the first chamber 101 includes at least one of hydrofluoric acid (HF), nitric acid (HNO3), phosphoric acid, and acetic acid, and the alkaline solution in the second chamber 102 includes at least one of potassium hydroxide, tetramethylammonium hydroxide (TMAH), and ammonium hydroxide. This application does not limit the etching time of the acidic and alkaline solutions on the wafer; the etching times of the acidic and alkaline solutions on the wafer can be similar or the same. In this embodiment, taking the solution in the first chamber 101 as an example of HF and HNO3, and the solution in the second chamber 102 as an example of TMAH, the etching time of the acidic and alkaline solutions on the wafer is, for example, the same. This invention does not limit the selection of etching solutions; in other embodiments, other etching solutions can be selected according to the wet etching process.

[0030] Please see Figures 1 to 2As shown, in one embodiment of this utility model, different etching chambers simultaneously output waste liquid, and the waste liquid output from different etching chambers simultaneously arrives at the subsequently installed heat exchange equipment 20, so as to facilitate the mixing and reaction of the waste liquid in the subsequently installed heat exchange equipment 20. In this application, the steps of processing wafers in the etching chambers can be adaptively adjusted so that different etching chambers can discharge waste liquid synchronously. In this embodiment, the steps of processing wafers in the etching chambers are performed, for example, in the following order. First, the first wafer is etched in the first chamber 101, while no etching is performed in the second chamber 102. After the first wafer in the first chamber 101 is etched, the first wafer is placed in the second chamber 102 for etching, and at the same time, the next wafer, namely the second wafer, is placed in the first chamber 101. The second wafer in the first chamber 101 and the first wafer in the second chamber 102 are etched synchronously and the etching ends synchronously. After etching, the first wafer undergoes two etching steps and is removed from the second chamber 102. The first wafer is then etched. Next, the second wafer is removed from the first chamber 101 and placed into the second chamber 102. Simultaneously, the third wafer is placed into the first chamber 101. The third wafer in the first chamber 101 and the second wafer in the second chamber 102 are etched synchronously and their etching processes terminate synchronously. These steps are repeated until all wafers have been etched. After all wafers have been etched, waste liquid is simultaneously discharged from both the first chamber 101 and the second chamber 102. These wafer processing steps accelerate the wafer etching speed, improve etching efficiency, and save etching time.

[0031] Please see Figure 1 As shown, in one embodiment of this utility model, the heat exchange device 20 is connected to multiple etching chambers, providing a site for the mixing and reaction of waste liquids discharged from the multiple etching chambers. In this embodiment, the first chamber 101 and the second chamber 102 are each connected to the heat exchange device 20, which is, for example, a type of indirect heat exchanger. Indirect heat exchangers include, for example, shell-and-tube heat exchangers, coiled tube heat exchangers, spiral wound tube heat exchangers, plate heat exchangers, jacketed heat exchangers, spray heat exchangers, and shell-and-tube heat exchangers.

[0032] Please see Figure 1 As shown, in one embodiment of this utility model, the heat exchange device 20 includes, for example, a cavity 201 and a heat exchange pipe 202. The cavity 201 includes, for example, a top 2011 and a bottom 2012 disposed opposite to each other. In this embodiment, the first waste liquid 1011 discharged from the first chamber 101 and the second waste liquid 1021 discharged from the second chamber 102 each enter the cavity 201. The first waste liquid 1011 and the second waste liquid 1021 undergo a mixing and neutralization reaction in the cavity 201, producing a mixed gas and a third waste liquid. The reaction equation is, for example, H2. + +NO3 - +(CH3)4N ++OH - →H2O+CO X +NO X The flow rate of the first waste liquid 1011 discharged from the first chamber 101 is, for example, 1000 mL / min-2000 mL / min, and the flow rate of the second waste liquid 1021 discharged from the second chamber 102 is, for example, 2000 mL / min-4000 mL / min. The mixed gas includes, for example, carbon oxides (CO). x ) and nitrogen oxides (NO) x ), etc., the third type of waste liquid is, for example, neutral waste liquid, etc.

[0033] Please see Figure 1 As shown, in one embodiment of this utility model, a heat exchange pipe 202 is disposed within a cavity 201. In this embodiment, when the first waste liquid 1011 and the second waste liquid 1021 mix and react in the cavity 201, a large amount of heat is generated. Therefore, a heat exchange medium 2021 flows through the heat exchange pipe 202 to remove the heat generated by the reaction of the first waste liquid 1011 and the second waste liquid 1021, thereby achieving the purpose of heat recovery and improving energy utilization. The heat released by the reaction of the first waste liquid 1011 discharged from the first cavity 101 and the second waste liquid 1021 discharged from the second cavity 102 is, for example, 100 KJ / min-300 KJ / min. The heat exchange pipe 202 is, for example, one of a straight pipe, a U-shaped pipe, a spiral coil, or a serpentine tube. The heat exchange medium 2021 is, for example, water, gas, or organic matter. In this embodiment, the heat exchange pipe 202 is, for example, a spiral coil, to increase the contact area between the heat exchange medium 2021 in the heat exchange pipe 202 and the first waste liquid 1011 and the second waste liquid 1021 in the cavity 201, thereby improving the heat exchange efficiency. The heat exchange medium 2021 is, for example, water. The heat released by the reaction between the first waste liquid 1011 discharged from the first cavity 101 and the second waste liquid 1021 discharged from the second cavity 102 can, for example, raise the temperature of water at 20°C to 30°C-200°C.

[0034] Please see Figure 1 As shown, in one embodiment of this invention, the reactor 30 and the heat exchange device 20 are connected. Specifically, the reactor 30 is connected to the heat exchange device 20 via a top 2011. In this embodiment, the mixed gas generated from the reaction of the first waste liquid 1011 and the second waste liquid 1021 contains toxic CO. x and NO x Therefore, the mixed gas is introduced into the reactor for further reaction to remove the toxic CO from the mixed gas. x and NO x The toxic CO2 and N2 are converted into harmless CO2 and N2, further reducing the environmental pollution and harm caused by the wet etching system. In this embodiment, a catalyst 301 is also provided in the reactor 30 to convert the toxic CO2 into harmless N2. x and NOx Under the action of catalyst 301, it is converted into harmless CO2 and N2. The specific reaction equation is as follows: CO X +NO X →CO2 + N2, catalyst 301 includes at least one of iron-based, cobalt-based, and copper-based metal oxides, and the reaction temperature is, for example, 100℃-400℃. In other embodiments of this invention, the reaction temperature can be greater than 400℃ to increase the CO concentration in the mixed gas. x and NO x This improves the conversion rate and further enhances the cleanliness and harmlessness of the wet etching system.

[0035] Please see Figure 1 As shown, in one embodiment of this invention, the wet etching system further includes a liquid discharge pipe 40, which is connected to the heat exchange device 20 via a bottom 2012. In this embodiment, the first waste liquid 1011 and the second waste liquid 1021 mix and react within the cavity 201 to generate a neutral waste liquid, which flows out of the wet etching system through the liquid discharge pipe 40. Compared to the wet etching system directly outputting the second waste liquid 1021 and the first waste liquid 1011, the wet etching system provided by this invention directly outputs the neutral waste liquid generated by the reaction of the second waste liquid 1021 and the first waste liquid 1011. The neutral waste liquid has low hazard, thereby reducing the environmental harm and pollution caused by the wet etching system.

[0036] In summary, this invention provides a wet etching system that, through the sequential connection of etching chambers, heat exchange equipment, and reactors, treats waste acid and alkali, outputting neutral waste liquid and harmless gas. This avoids the direct output of highly hazardous waste liquids such as waste acid and alkali from wet etching systems, reducing the environmental harm and pollution caused by wet etching. Furthermore, the wet etching system provided by this invention can recover the heat generated by the reaction of waste acid and alkali, avoiding heat waste and improving energy utilization efficiency.

[0037] The embodiments of this utility model disclosed above are merely illustrative of the present utility model. The embodiments do not exhaustively describe all details, nor do they limit the utility model to the specific implementations described. Obviously, many modifications and variations can be made based on the content of this specification. This specification selects and specifically describes these embodiments to better explain the principles and practical applications of this utility model, thereby enabling those skilled in the art to better understand and utilize it. This utility model is limited only by the claims and their full scope and equivalents.

Claims

1. A wet etching system, characterized in that, At least including: Multiple etching chambers, each discharging waste liquid; A heat exchange device is connected to multiple etching chambers, and the waste liquid is mixed and reacted within the heat exchange device; as well as The reactor is connected to the heat exchange equipment.

2. The wet etching system according to claim 1, characterized in that, The acidity or alkalinity of the waste liquid output from at least one of the etching chambers differs from that of the waste liquid output from the other etching chambers.

3. The wet etching system according to claim 1, characterized in that, The waste liquid output from multiple etching chambers simultaneously arrives at the heat exchanger.

4. The wet etching system according to claim 1, characterized in that, The heat exchange device includes a cavity in which the waste liquid is mixed and reacted.

5. The wet etching system according to claim 4, characterized in that, The heat exchange equipment also includes heat exchange pipes, which are disposed within the cavity.

6. The wet etching system according to claim 5, characterized in that, The heat exchange pipes are straight pipes, U-shaped pipes, spiral coils, or serpentine pipes.

7. The wet etching system according to claim 4, characterized in that, The cavity includes a top and a bottom disposed opposite each other, and the reactor is connected to the heat exchange device through the top.

8. The wet etching system according to claim 7, characterized in that, The wet etching system also includes a liquid discharge pipe, which is connected to the heat exchange device via the bottom.

9. The wet etching system according to claim 1, characterized in that, The reactor contains a catalyst.

10. The wet etching system according to claim 1, characterized in that, The heat exchange equipment is one type of indirect heat exchanger, which includes shell-and-tube heat exchangers, coiled tube heat exchangers, spiral wound tube heat exchangers, plate heat exchangers, jacketed heat exchangers, spray heat exchangers, and shell-and-tube heat exchangers.

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