Etching equipment

Abstract

The utility model discloses etching equipment, and relates to the field of semiconductor processing equipment, and the equipment comprises a slide holder, the upper surface of which is provided with a first region and a second region surrounding the first region; the first area is used for placing a to-be-etched part; the cavity cover structure can be covered above the slide holder, and a sealed etching cavity is formed by the cavity cover structure and the slide holder; the nozzle structure is mounted in the second area and is used for spraying etching gas into the etching cavity; and the air exhaust structure is installed on the upper surface of the cavity cover structure, communicates with the etching cavity and is used for exhausting etching waste gas in the etching cavity, and an air exhaust pipe, extending into the etching cavity, of the air exhaust structure can adjust the exhaust height relative to the part to be etched. The etching waste gas generated in the etching process can be discharged out of the etching cavity in time, and the etching uniformity of the to-be-etched part can be ensured; due to the fact that uniform etching of the to-be-etched part can be achieved, the metal contamination condition of the to-be-etched part can be reflected more accurately.

Description

Technical Field

[0001] The present application relates to the field of semiconductor processing equipment, and in particular to an etching equipment. Background Art

[0002] Driven by the strong momentum of Moore's Law, high-performance, low-power chips based on the 7nm technology generation, mainly based on Fin Field Effect Transistors (FinFETs), have long been integrated into today's smartphones. To manufacture such powerful chips, a large number of new chemical elements need to be introduced. Each technology generation introduces different chemical elements to meet the improvement of chip performance. For example, the introduction of hafnium (Hf) ushered in the era of high-k metal gates. The introduction of different chemical elements also increases the difficulty of controlling metal contamination in the chip manufacturing process. The vapor phase decomposition metal contamination collection system (VPD) combined with the inductively coupled plasma mass spectrometer (ICP-MS) is currently a common method for detecting metal contamination. Its sensitivity can increase the detection sensitivity of various elements to 1×10 6 atoms / cm 2 ~1×10 7 atoms / cm 2 .

[0003] On the other hand, to meet the needs of manufacturing advanced device generations, contamination analysis has expanded beyond conventional silicon oxide and silicon nitride to include silicon (including doped) and silicon germanium epitaxial layers. Therefore, conventional hydrogen fluoride (HF) vapor phase etching cannot meet the requirements for etching bulk silicon layers. To address the 0.5μm to 5μm bulk silicon layer etching process, the industry has developed a technique that introduces both HF vapor and an oxidizing gas into the vapor phase etching chamber to etch bulk silicon. The oxidizing gas oxidizes the silicon into silicon oxide, while the HF vapor etches the silicon oxide, achieving bulk silicon etching. This technique requires the etchant to effectively collect the exhaust gases generated during the etching process. Therefore, integrating exhaust gas collection capabilities into the etchant is a pressing issue. Utility Model Content

[0004] In view of the above problems, the present application provides an etching device to achieve the purpose of integrating etching waste gas collection in the etching device. The specific solution is as follows:

[0005] An etching device, comprising:

[0006] A wafer stage, wherein the upper surface of the wafer stage has a first area and a second area surrounding the first area; the first area is used to place the workpiece to be etched;

[0007] A cavity cover structure, which can cover the top of the wafer stage to form a sealed etching cavity with the wafer stage;

[0008] A nozzle structure is installed in the second region and used to spray etching gas into the etching cavity.

[0009] A pumping structure is installed on the upper surface of the cavity cover structure and communicates with the etching cavity and used to discharge etching waste gas in the etching cavity; wherein the pumping tube extending into the etching cavity can adjust the exhaust height relative to the etching piece.

[0010] Optionally, the etching device further comprises a lifting device, the cavity cover structure is installed on the lifting device, and the lifting device can drive the cavity cover structure to move in the vertical direction so as to combine the cavity cover structure with the wafer table to form the etching cavity or separate the cavity cover structure from the wafer table to take or place the etching piece.

[0011] Optionally, the etching device comprises:

[0012] A base is fixedly installed in the second region; the base has a first gas pipeline; the wafer table has a second gas pipeline, one end of the second gas pipeline is connected to the gas inlet installed on the lower surface of the wafer table, and the other end communicates with the first gas pipeline;

[0013] A gas nozzle is installed on the base through an adjusting structure and communicates with the first gas pipeline;

[0014] The adjusting structure is used to adjust the height of the gas nozzle relative to the wafer table and / or the orientation of the jet port of the gas nozzle.

[0015] Optionally, the etching device comprises a first end and a second end, the first end and the second end have a third gas pipeline therebetween, the first end communicates with the first gas pipeline through the adjusting structure, and the second end has a jet port used to spray etching gas into the etching cavity;

[0016] The third gas pipeline is a pipeline with uniform aperture;

[0017] Or, in the gas transmission path from the first end to the second end, the third gas pipeline comprises a first sub-pipeline and a second sub-pipeline, the aperture of the first sub-pipeline gradually decreases from a first size to a second size, and the aperture of the second sub-pipeline is the second size.

[0018] Optionally, the second size is in the range of 0.5mm to 6mm.

[0019] Optionally, the adjusting structure is any one of a bellows and a spring piece;

[0020] Or, the gas nozzle and the base further have a sealing piece therebetween.

[0021] Optionally, in the etching device, a plurality of nozzle structures are arranged in the second area, and the nozzle structures are distributed around the first area.

[0022] Optionally, in the etching device, the gas extraction structure comprises:

[0023] a gas extraction pipe penetrating through the cavity cover structure, and an upper end of the gas extraction pipe being communicated with a gas extraction pump;

[0024] a motor installed above the gas extraction pipe, and the motor being used to adjust the height of a lower end of the gas extraction pipe relative to the etching object.

[0025] Optionally, in the etching device, the lower end of the gas extraction pipe has a plurality of first gas extraction holes.

[0026] Optionally, in the etching device, the sidewall of the lower end of the gas extraction pipe has a plurality of second gas extraction holes.

[0027] By means of the above technical solution, in the etching device provided by the present application, the nozzle structure is arranged in the second area of the wafer stage, which can be used to spray etching gas into the etching cavity, so that the etching object placed on the first area of the wafer stage can be etched by the etching gas, and the etching waste gas generated in the etching process can be discharged out of the etching cavity through the gas extraction structure installed above the cavity cover structure.

[0028] The technical solution of the present application can timely discharge the etching waste gas generated in the etching process to the outside of the etching cavity, accurately control the internal etching gas environment, and ensure the uniformity of etching of the etching object. In addition, a container directly communicating with the gas extraction structure can be arranged outside the etching device to collect the etching waste gas, so as to realize the collection of the etching waste gas in the etching device and achieve better collection efficiency of the etching waste gas. In addition, the uniform etching of the etching object can more accurately reflect the metal contamination of the etching object. For example, when the etching device is used to etch bulk silicon, the etching of the bulk silicon can be more uniform, the etching uniformity is good, the metal ions in the bulk silicon can be efficiently collected, and thus the metal contamination in the bulk silicon can be characterized and analyzed. Therefore, the etching device provided by the present application can be used to etch the etching object, and better etching effect can be achieved.

[0029] In addition, the gas extraction pipe of the gas extraction structure extending to the etching cavity can adjust the exhaust height relative to the etching object, so that the etching device can adjust the exhaust effect according to different etching parameters, and more uniform etching effect can be achieved. BRIEF DESCRIPTION OF DRAWINGS

[0030] In order to more clearly illustrate the technical solutions in the embodiments of the present application or related technologies, the following briefly introduces the drawings required for use in the embodiments or descriptions of the prior art. Obviously, the drawings described below are merely embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on the provided drawings without any creative work.

[0031] The structures, proportions, sizes, etc. depicted in the drawings of this specification are only used to match the contents disclosed in the specification so as to facilitate understanding and reading by persons familiar with this technology. They are not intended to limit the conditions under which this application can be implemented, and therefore have no substantive technical significance. Any structural modifications, changes in proportional relationships, or adjustments in size, without affecting the efficacy and objectives that can be achieved by this application, should still fall within the scope of the technical contents disclosed in this application.

[0032] Figure 1 A schematic structural diagram of an etching device provided in an embodiment of the present application;

[0033] Figure 2 A top view of the upper surface of a wafer stage provided in an embodiment of the present application;

[0034] Figure 3 A cross-sectional view of a nozzle structure provided in an embodiment of the present application;

[0035] Figure 4 for Figure 3 A top plan view of the nozzle structure shown;

[0036] Figure 5 A cross-sectional view of an exhaust pipe provided in an embodiment of the present application;

[0037] Figure 6 for Figure 5 A partially enlarged top view of the lower end face of the exhaust pipe is shown;

[0038] Figure 7 for Figure 5 A partial enlarged view of the exhaust pipe near the lower end side wall is shown;

[0039] Figure 8 Schematic diagram of the working principle of etching operation performed by the etching equipment provided in an embodiment of the present application.

[0040] Reference numerals:

[0041] 100-chamber cover structure; 200-stage; 201-lower surface of stage; 300-nozzle structure; 301-air nozzle; 302-base; 303-seal; 304-adjustment structure; 305-third gas pipeline; 301a-first gas pipeline; 301b-first sub-pipeline; 301c-wedge-shaped blocking structure; 301d-second sub-pipeline; 400-exhaust structure; 401-motor; 402-exhaust pipe; 402a-exhaust port; 402b-bellows; 402c-first exhaust hole; 402d-sealing groove; 402e-second exhaust hole; 403-exhaust pump; 500-lifting device; 201-lower surface of stage; 202-air inlet; 601-first area; 602-second area. DETAILED DESCRIPTION

[0042] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the embodiments of the present application. Those skilled in the art will know that with the development of technology and the emergence of new scenarios, the technical solutions provided in the embodiments of the present application are also applicable to similar technical problems.

[0043] In etching equipment, on the one hand, if the etching waste gas cannot be discharged in time, the concentration of the etching gas in the etching chamber will be affected, which will in turn affect the etching uniformity and the etching quality. On the other hand, if the etching waste gas cannot be collected in a timely and effective manner, the etching uniformity will be affected, which will in turn affect the analysis results of the metal contamination of the etched part.

[0044] In order to timely and effectively discharge and collect the etching waste gas generated during the etching process, an embodiment of the present application provides an etching device, which includes:

[0045] A wafer stage, wherein the upper surface of the wafer stage has a first area and a second area surrounding the first area; the first area is used to place the workpiece to be etched;

[0046] A cavity cover structure, which can cover the top of the wafer stage to form a sealed etching cavity with the wafer stage;

[0047] A nozzle structure is installed in the second area and is used to spray etching gas into the etching chamber;

[0048] The exhaust structure is installed on the upper surface of the chamber cover structure and is connected to the etching chamber to exhaust the etching waste gas in the etching chamber. The exhaust pipe extending from the exhaust structure into the etching chamber can adjust the exhaust height relative to the workpiece to be etched.

[0049] In the etching equipment provided in the embodiment of the present application, a nozzle structure is installed in the second area of ​​the wafer stage, which can be used to spray etching gas into the etching chamber, and then the etching gas can be used to etch the workpiece to be etched placed on the first area of ​​the wafer stage. The etching waste gas generated during the etching process can be discharged from the etching chamber through the exhaust structure installed above the cavity cover structure.

[0050] Based on the above description, it can be known that the etching equipment can discharge the etching waste gas generated during the etching process to the outside of the etching chamber in a timely manner, and can accurately control the internal etching gas environment to ensure the uniformity of etching of the part to be etched. Moreover, a container directly connected to the exhaust structure can be set outside the etching equipment to collect the etching waste gas, which is convenient for collecting the etching waste gas in the etching equipment and achieving better collection efficiency of the etching waste gas. In addition, the uniform etching of the part to be etched can also more accurately reflect the metal contamination of the part to be etched. Therefore, by using the etching equipment provided in the embodiment of the present application to etch the part to be etched, a better quality etching effect can be achieved.

[0051] In order to make the above-mentioned purposes, features and advantages of the present application more obvious and easy to understand, the present application is further described in detail below with reference to the accompanying drawings and specific embodiments.

[0052] refer to Figure 1 and Figure 2 , Figure 1 A schematic structural diagram of an etching device provided in an embodiment of the present application is shown in FIG. Figure 2 This is a top view of the upper surface of a wafer stage provided in an embodiment of the present application. Figure 1 This is a cross-sectional view of the etching equipment along the height direction.

[0053] like Figure 1 and Figure 2 As shown, the etching equipment includes:

[0054] The wafer stage 200 has an upper surface having a first area and a second area 602 surrounding the first area 601; the first area 601 is used to place the workpiece to be etched, which is not shown in the drawings of the embodiment of the present application;

[0055] The cavity cover structure 100 can cover the top of the wafer stage 200 to form a sealed etching cavity with the wafer stage 200;

[0056] The nozzle structure 300 is installed in the second area 602 and is used to spray etching gas into the etching chamber; Figure 2 The middle arrow is used to indicate the injection direction of the etching gas;

[0057] The exhaust structure 400 is installed on the upper surface of the chamber cover structure 100 and is connected to the etching chamber to exhaust the etching waste gas in the etching chamber.

[0058] Optionally, the exhaust pipe 402 extending from the exhaust structure 400 into the etching chamber can be adjusted in height relative to the workpiece to be etched. In other words, the exhaust pipe 402 can be adjusted in height in the vertical direction to adjust its height relative to the workpiece to be etched. By adjusting the exhaust height of the exhaust pipe 402, the exhaust effect can be optimized, allowing the etching equipment to adjust the exhaust effect according to different etching parameters, thereby achieving a more uniform etching effect.

[0059] The object to be etched may be a semiconductor wafer, including but not limited to a silicon wafer, a silicon carbide wafer, and a gallium arsenide wafer. The object to be etched may also be a glass plate, a sapphire substrate, or a ceramic substrate. The present embodiment of the present application does not limit the material of the object to be etched.

[0060] The etching gas ejected by the nozzle structure 300 may be a mixed gas including hydrogen fluoride vapor. The transmission direction of the etching gas may be as follows: Figure 1 As shown by the middle arrow, the etching gas ejected by the nozzle structure 300 is ejected from the edge of the wafer stage 200 toward the central area, and then discharged from the etching chamber above the central area through the exhaust structure 400.

[0061] When the etching gas is input from the edge of the wafer stage 200, if there is no exhaust in the central area, the etching gas will move irregularly in the etching chamber. After the etching gas reaches saturation inside the etching chamber, the airflow will be relatively stable, and it will be difficult for the airflow to diffuse to the central area of ​​the wafer stage 200, thereby causing the problem of localized uneven etching, which is particularly obvious in the central area. The embodiment of the present application can achieve exhaust above the central area of ​​the wafer stage 200 through the exhaust structure 400. The etching gas in the edge area of ​​the wafer stage 200 will continue to diffuse toward the central area, which can better achieve uniform etching of the entire surface of the workpiece to be etched.

[0062] In the embodiment of the present application, the etching equipment can discharge the etching waste gas generated during the etching process to the outside of the etching chamber in a timely manner through the exhaust structure 400, and can accurately control the internal etching gas environment to ensure the uniformity of etching of the part to be etched. In addition, a container directly connected to the exhaust structure 400 can be set outside the etching equipment to collect the etching waste gas, which is convenient for collecting the etching waste gas in the etching equipment and achieving better collection efficiency of the etching waste gas. For the uniform etching of the part to be etched, the etching uniformity can be more accurately analyzed, and the metal contamination of the part to be etched can be more accurately reflected. Therefore, by using the etching equipment provided in the embodiment of the present application to etch the part to be etched, a better quality etching effect can be achieved.

[0063] To reduce contamination of the etched parts by foreign materials, PVDF is recommended based on material purity and economic considerations. However, this is not limiting; similar corrosion-resistant, high-purity fluororesin materials can be used. In this embodiment, the cavity cover structure 100 is a PVDF (polyvinylidene fluoride) cover, meaning that the cavity cover structure 100 can be made of high-purity PVDF. PVDF has excellent chemical resistance, resisting most acid and alkali erosion, and possesses good mechanical strength and plasticity, allowing it to be processed into various shapes as required.

[0064] The cavity cover structure 100 is prepared using PVDF material. Based on the chemical corrosion resistance of PVDF material, it can prevent the etching gas from corroding the cavity cover structure 100, and can also prevent the cavity cover structure 100 from producing pollutants that contaminate the etched parts due to corrosion; and based on the good plasticity of PVDF material, the required shape structure can be prepared to be suitable for etching equipment with different shape requirements.

[0065] In the embodiment of the present application, the cavity cover structure 100 is not limited to a PVDF cover, but can also be a cover structure of other materials, such as a ceramic cover or a silicon carbide cover, etc. The embodiment of the present application does not limit the material of the cavity cover structure 100.

[0066] Optionally, the periphery of the cavity cover structure 100 may be a cylindrical structure, and the lower surface may be a dome-shaped structure. The air extraction structure 400 is installed on the upper surface of the cavity cover structure 100 .

[0067] In one embodiment of the present application, the etching apparatus further includes a lifting device 500. The chamber cover structure 100 is mounted on the lifting device 500. The lifting device 500 can drive the chamber cover structure 100 to move vertically, so that the chamber cover structure 100 can be closed with the wafer stage 200 to form an etching chamber, or separated from the wafer stage 200 to take / place the object to be etched. The chamber cover structure 100 and the exhaust structure 400 can be controlled by the lifting device.

[0068] The lifting device 500 can automatically control the rise and fall of the chamber cover structure 100, and facilitate the control of the covering or separation of the chamber cover structure 100 and the wafer stage 200.

[0069] Optionally, the lifting device may be a cylinder or a motor. The embodiment of the present application does not limit the implementation of the lifting device 500 and is not limited to an electrically controlled lifting device, but may also be a mechanical manual lifting device.

[0070] Similarly, in order to reduce the pollution of the foreign material to the to-be-etched piece, the carrier table 200 can be a PVDF platform. In the embodiment of the present application, the carrier table 200 is not limited to the PVDF platform, and can also be a platform made of other materials, such as a ceramic platform, or a silicon carbide platform, or a fluorine-containing resin platform, etc. The platforms made of the above-mentioned materials all have good corrosion resistance, and the material of the carrier table 200 is not limited in the embodiment of the present application.

[0071] The carrier table 200 can be compatible with non-contact etching of a 6-inch, 8-inch, and 12-inch wafer as the to-be-etched piece. The to-be-etched piece is fixed on the upper surface of the carrier table 200 by a clamp, and non-contact etching is achieved by etching gas, and the etching process does not need to be in direct physical contact with the to-be-etched piece.

[0072] In the embodiment of the present application, a cooling pipeline is arranged inside the carrier table 200 for transmitting cooling liquid. The cooling liquid in the cooling pipeline is controlled by an external temperature circulation controller. When the to-be-etched piece is a structure such as a bulk silicon that will release heat during etching, based on the cooling liquid in the cooling pipeline, the surface temperature of the carrier table 200 can be accurately controlled, and then the temperature of the to-be-etched piece placed on the carrier table 200 can be controlled, and then the temperature of the chemical reaction on the surface of the to-be-etched piece during etching can be controlled to be constant, so as to ensure the etching quality.

[0073] In the embodiment of the present application, as shown in Figure 2 A plurality of nozzle structures 300 are arranged in the second area 602, and the nozzle structures 300 are distributed around the first area 601. According to the etching requirement, 2-6 nozzle structures 300 can be installed in the second area 602, such as 4 nozzle structures 300 can be installed in the second area 602. The etching gas injection port of the nozzle structure 300 faces the center area of the first area 601, so that more etching gas can be sprayed to the surface of the to-be-etched piece placed on the first area 601, and the etching rate and etching quality of the to-be-etched piece can be improved.

[0074] Optionally, a plurality of nozzle mounting structures can be arranged in the second area, and each nozzle mounting structure can be used to install one nozzle structure 300. In the embodiment of the present application, according to the etching requirement, the nozzle structure can be installed on part of the nozzle mounting structures, or the nozzle structure 300 can be installed on all the nozzle mounting structures, so as to provide etching gas by adapting the number and distribution of the nozzle structures 300 according to different etching conditions, and to ensure the etching quality.

[0075] Referring to Figure 3 and Figure 4 , Figure 3 a sectional view of a nozzle structure provided in the embodiment of the present application is shown, Figure 4 a top view of the top of the nozzle structure is shown in Figure 3 . Among them, Figure 3It is a cross-sectional view of the nozzle structure 300 along the height direction.

[0076] Combine Figures 1-4 As shown, the nozzle structure includes: a base 302, which is fixedly mounted in the second region 602; a first gas conduit 301a on the base 302; a second gas conduit 301a in the wafer stage 200 (the second gas conduit is not shown in the drawings of the present embodiment); one end of the second gas conduit is connected to the gas inlet 202 mounted on the lower surface 201 of the wafer stage, and the other end is connected to the first gas conduit 301a; and an air nozzle 301, which is mounted on the base 302 via an adjustment structure 304 and connected to the first gas conduit 301a. The adjustment structure 304 is used to adjust the height of the air nozzle 301 relative to the wafer stage 200 and / or the direction of the air nozzle 301's jet. The nozzle structure 300 is connected to the gas inlet 202 mounted on the lower surface 201 of the wafer stage, and can introduce externally provided etching gas through the gas inlet 202.

[0077] Optionally, the adjustment structure 304 is any one of a bellows and an elastic body, wherein the elastic body can be a spring, a shrapnel, etc.

[0078] The air nozzle 301 is mounted on the base 302 via an adjustment structure 304 . The adjustment structure 304 allows the air nozzle 301 to move relative to the base 302 to adjust the height of the air nozzle 301 relative to the wafer stage 200 and / or the direction of the jet outlet of the air nozzle 301 .

[0079] Based on the above embodiment, a sealing member 303 is further provided between the air nozzle 301 and the base 302 to improve the air tightness of the gas pipeline in the nozzle structure 300. Optionally, the sealing member 303 may be a sealing ring.

[0080] like Figure 3 As shown, the air nozzle 301 includes a first end ( Figure 1 The upper end of the middle air nozzle 301) and the second end ( Figure 1 The lower end of the middle air nozzle 301), a third gas pipeline 305 is provided between the first end and the second end, the first end is connected to the first gas pipeline 301a through the adjustment structure 304, and the second end has an injection port for injecting etching gas into the etching chamber. Figure 3 The arrow in the middle is used to indicate the injection direction of the etching gas.

[0081] Figure 3In the illustrated embodiment, along the gas transmission path from the first end to the second end, the third gas conduit 305 includes a first sub-conduit 301b and a second sub-conduit 301d. The aperture of the first sub-conduit 301b gradually decreases from a first size to a second size, while the aperture of the second sub-conduit 301d remains at the second size. In this embodiment, the first sub-conduit 301b has a bell-mouth structure, with a larger aperture at the end closest to the gas source (the first size) and a smaller aperture at the end further from the gas source (the second size). This increases the gas pressure in the third gas conduit 305, thereby enabling the etching gas to be ejected from the nozzle 301.

[0082] Optionally, the second sub-channel 302d is a cylindrical channel with a second size aperture, and the aperture of the second sub-channel 302d is uniform and constant. The second size may range from 0.5 mm to 6 mm.

[0083] In other embodiments, the third gas conduit 305 may also be a conduit with a uniform pore size. In this embodiment, the third gas conduit 305 is a cylindrical conduit with a uniform pore size, which facilitates the process preparation of the third gas conduit 305. In this case, to achieve the effect of ejecting the etching gas from the nozzle 301, the pressure of the gas source outside the etching equipment can be increased.

[0084] like Figure 3 As shown, the top of the nozzle structure 300 has a wedge-shaped blocking structure 301c, which has an inclined surface and can change the spray direction of the etching gas transmitted vertically upward, so that more etching gas is sprayed toward the surface of the to-be-etched workpiece on the first area 601, thereby improving the etching rate and etching quality.

[0085] In the etching equipment, the exhaust structure 400 is installed above the chamber cover structure 100. Optionally, the exhaust structure 400 can be installed in the top center area of ​​the chamber cover structure 100 to more evenly and quickly extract and discharge the etching waste gas inside the etching chamber.

[0086] like Figure 1 As shown, the exhaust structure 400 includes an exhaust pipe 402 that extends through the chamber cover structure 100; an exhaust pump 403 connected to the upper end of the exhaust pipe 402; and a motor 401 mounted above the exhaust pipe 402. The motor 401 is used to adjust the height of the lower end of the exhaust pipe 402 relative to the workpiece to be etched. By controlling the power of the exhaust pump 403, the exhaust rate of the exhaust structure 400 from the etching chamber can be controlled to maintain a slightly negative pressure environment within the etching chamber. The exhaust gas in the etching chamber is promptly discharged to the outside of the etching chamber to ensure etching uniformity and quality.

[0087] Since the exhaust pipe 402 passes through the chamber cover structure 100, the lower end of the exhaust pipe 402 is located in the etching chamber; the upper end of the exhaust pipe 402 is located above the chamber cover structure 100, and the upper end of the exhaust pipe 402 is fixed with a motor 401 and connected to the exhaust pump 403. In this way, the exhaust pump 403 can not only extract the etching waste gas from the etching chamber, but also drive the exhaust pipe 402 to move vertically by the motor 401.

[0088] In the etching apparatus, the motor 401 can be used to control the vertical movement of the exhaust pipe 402, thereby controlling the upward and downward expansion and contraction of the exhaust pipe 402, thereby controlling the distance between the lower end of the exhaust pipe 402 and the underlying object to be etched. During the etching process, the distance between the lower end of the exhaust pipe 402 and the object to be etched can be set in the range of 5mm to 30mm.

[0089] Optionally, the exhaust structure 400 can be arranged to be located in the central area of ​​the upper surface of the cavity cover structure 100, so that during the etching process, the lower end of the exhaust pipe 402 can be located above the central area of ​​the workpiece to be etched, and the distance between the lower end of the exhaust pipe 402 and the center of the workpiece to be etched is adjusted by the motor 401. Not only can the etching waste gas formed during the etching process of the workpiece to be etched be discharged to the outside of the etching cavity in time, but the micro-negative pressure formed when the etching waste gas is extracted and discharged through the exhaust pipe 402 can also lead more etching gas to the surface of the workpiece to be etched in time, which can improve the etching uniformity, increase the etching rate, and perform a more accurate analysis of the etching uniformity, and can also more accurately reflect the metal contamination of the workpiece to be etched.

[0090] refer to Figure 5-Figure 7 , Figure 5 A cross-sectional view of an exhaust pipe provided in an embodiment of the present application, Figure 6 for Figure 5 The enlarged top view of the lower end of the exhaust pipe is shown. Figure 7 for Figure 5 The enlarged view of the exhaust pipe near the lower end side wall is shown. Figure 5 It is a cross-sectional view of the exhaust pipe 402 along the height direction.

[0091] The upper end of the exhaust pipe 402, located outside the etching chamber, has an exhaust port 402a. This port 402a is connected to an exhaust pump 403, which extracts and discharges the etching waste gas. A retractable bellows 402b is provided between the upper and lower ends of the exhaust pipe 402. A sealing groove 402d is provided between the upper and lower ends of the exhaust pipe 402 to improve the airtightness between the exhaust pipe 402 and the chamber cover structure 100.

[0092] like Figure 5-Figure 7As shown, the lower end surface of the exhaust pipe 402 has a plurality of first exhaust holes 402c. The lower end sidewall of the exhaust pipe 402 has a plurality of second exhaust holes 402e. The first exhaust holes 402c and the second exhaust holes 402e can be circular holes, square holes, triangular holes, or other geometric hole structures. The present embodiment does not limit the shapes of the first exhaust holes 402c and the second exhaust holes 402e.

[0093] To facilitate the process preparation of the exhaust pipe 402, multiple first exhaust holes 402c can be set with the same shape and size, and the second exhaust holes 402e can be set with the same shape and size. The shapes of the first exhaust holes 402c and the second exhaust holes 402e can be the same or different.

[0094] Multiple first exhaust holes 402c are evenly distributed in the lower end surface of the exhaust pipe 402. Compared with directly setting a large-sized exhaust hole with the same aperture as the exhaust pipe 402 on the lower end surface, it can ensure the uniform discharge of etching waste gas to prevent large air flow fluctuations in the gas environment inside the etching chamber, thereby ensuring the stability of the etching environment and the etching quality.

[0095] Multiple second exhaust holes 402e are evenly distributed in the side wall of the lower end of the exhaust pipe 402. The multiple second exhaust holes 402e located around the side wall can evenly discharge the etching waste gas in multiple different directions in the horizontal direction. While increasing the exhaust rate of the etching waste gas, it can also avoid large airflow fluctuations in the gas environment inside the etching chamber, so as to ensure the stability of the etching environment and the etching quality.

[0096] In the embodiment of the present application, the exhaust holes can be arranged in the exhaust pipe 402 according to the needs, including but not limited to the methods provided in the embodiment of the present application. For example, the exhaust pipe 402 can be provided with a plurality of first exhaust holes 402c on the lower end surface alone, or a plurality of second exhaust holes 402e on the lower end side wall alone, or Figure 5 As shown, a plurality of first air extraction holes 402c are provided on the lower end surface, and a plurality of second air extraction holes 402e are provided on the lower end side wall.

[0097] It can be seen from the above description that the etching equipment provided in the embodiment of the present application can discharge the etching waste gas generated during the etching process to the outside of the etching chamber in a timely manner, and can accurately control the internal etching gas environment to ensure the etching uniformity of the part to be etched. In addition, a container directly connected to the exhaust structure 400 can be set outside the etching equipment to collect the etching waste gas, which is convenient for collecting the etching waste gas in the etching equipment and achieving better collection efficiency of the etching waste gas. For the uniform etching of the part to be etched, the etching uniformity can also be more accurately analyzed, and the metal contamination of the part to be etched can also be more accurately reflected. Therefore, by using the etching equipment provided in the embodiment of the present application to etch the part to be etched, a better quality etching effect can be achieved.

[0098] The following further describes the etching process of the etching device provided in the embodiment of the present application based on the etching device provided in the above embodiment.

[0099] refer to Figure 8 , Figure 8 A schematic diagram of the working principle of an etching device according to an embodiment of the present application performing an etching operation. The method for etching a workpiece by the etching device includes:

[0100] First, the calibration wafer is taken out from the calibration cassette by a robot and the position is corrected by a calibrator.

[0101] Then, the chamber cover structure 100 of the etching equipment is opened, and the workpiece to be etched is transferred to the wafer stage 200 of the etching equipment by a robot.

[0102] Furthermore, the chamber cover structure 100 is covered on the wafer stage 200 by the lifting device 500 to form a closed etching chamber.

[0103] Furthermore, the etching gas is sprayed onto the wafer surface through the nozzle structure 300 .

[0104] Furthermore, the exhaust function of the exhaust structure 400 is turned on, and the distance from the lower end of the exhaust pipe 402 to the surface of the workpiece to be etched is increased to complete the etching of the workpiece to be etched.

[0105] Finally, after the etching is completed, the workpiece to be etched is taken out from the etching equipment and the metal contamination is collected by scanning.

[0106] Among them, take the silicon wafer as an example of the part to be etched. The metal contamination detection of the etched silicon wafer is carried out by the gas phase decomposition metal contamination collection system. After the silicon wafer passes through the gas phase decomposition corrosion chamber of the gas phase decomposition metal contamination collection system, the hydrophilicity of the silicon wafer surface can be changed, and the silicon wafer surface will be hydrophobic after etching. The better the hydrophobicity of the silicon wafer surface, the more conducive it is to collecting metal contamination. Therefore, the etching uniformity requirement is also high. Because when collecting metal contamination, it is necessary to spin-coat a reagent droplet with a volume of about 1 ml on the surface of the silicon wafer. When the etching uniformity is not good, that is, there will be local hydrophilicity on the surface of the silicon wafer, or it will appear uneven at the microscopic level. During the collection process, the liquid is easily lost, which will lead to collection failure.

[0107] The various embodiments in the specification of this application are described in a progressive, parallel, or progressive and parallel manner. Each embodiment focuses on the differences from other embodiments, and the same or similar parts between the various embodiments can be referenced to each other. The embodiments provided in the embodiments of this application can be combined with each other if there is no contradiction.

[0108] The terms "upper," "lower," "top," "bottom," "inner," "outer," and the like, indicating positions or locations, are based on the positions or locations shown in the accompanying drawings and are intended solely to facilitate and simplify the description of this application. They are not intended to indicate or imply that the devices or elements referred to must have a specific orientation, be constructed, or operate in a specific orientation. Therefore, they should not be construed as limitations on this application. When a component is considered to be "connected" to another component, it may be directly connected to the other component or there may be a centrally located component.

Claims

1. An etching device, characterized in that: include: A wafer stage, wherein the upper surface of the wafer stage has a first area and a second area surrounding the first area; The first area is used for placing the workpiece to be etched; a cavity cover structure, the cavity cover structure being capable of covering the top of the wafer stage to form a sealed etching cavity with the wafer stage; a nozzle structure, the nozzle structure being installed in the second area and being used for spraying etching gas into the etching chamber; An exhaust structure is installed on the upper surface of the chamber cover structure and is connected to the etching chamber, and is used to discharge the etching waste gas in the etching chamber; wherein the exhaust pipe extending from the exhaust structure to the etching chamber can adjust the exhaust height relative to the workpiece to be etched.

2. The etching device according to claim 1, characterized in that It also includes a lifting device, and the cavity cover structure is installed on the lifting device. The lifting device can drive the cavity cover structure to move in the vertical direction so that the cavity cover structure covers the wafer stage to form the etching cavity, or is separated from the wafer stage to take / place the part to be etched.

3. The etching equipment according to claim 1, characterized in that The nozzle structure comprises: A base, the base being fixedly mounted in the second area; the base having a first gas pipeline; the wafer stage having a second gas pipeline, one end of the second gas pipeline being connected to an air inlet mounted on the lower surface of the wafer stage, and the other end being in communication with the first gas pipeline; an air nozzle, the air nozzle being mounted on the base through an adjustment structure and being in communication with the first gas pipeline; Wherein, the adjustment structure is used to adjust the height of the air nozzle relative to the wafer stage and / or the direction of the jet outlet of the air nozzle.

4. The etching device according to claim 3, characterized in that: The air nozzle includes a first end and a second end, a third gas pipeline is provided between the first end and the second end, the first end is connected to the first gas pipeline through the adjustment structure, and the second end has an injection port for injecting the etching gas into the etching chamber; Wherein, the third gas pipeline is a pipeline with uniform pore diameter; Alternatively, on the gas transmission path from the first end to the second end, the third gas pipeline includes a first sub-pipeline and a second sub-pipeline, the aperture of the first sub-pipeline gradually decreases from a first size to a second size, and the aperture of the second sub-pipeline is the second size.

5. The etching device according to claim 4, characterized in that: The second size has a value range of 0.5 mm to 6 mm.

6. The etching equipment according to claim 3, characterized in that The adjustment structure is any one of a bellows and an elastic body; Alternatively, a sealing member is provided between the air nozzle and the base.

7. The etching device according to claim 1, characterized in that: A plurality of nozzle structures are disposed in the second area, and the nozzle structures are distributed around the first area.

8. The etching equipment according to claim 1, characterized in that The air extraction pipe passes through the cavity cover structure; the upper end of the air extraction pipe is connected to an air extraction pump; The exhaust structure further includes a motor, which is installed above the exhaust pipe; the motor is used to adjust the height of the lower end of the exhaust pipe relative to the workpiece to be etched.

9. The etching device according to claim 8, characterized in that: The lower end surface of the air extraction pipe is provided with a plurality of first air extraction holes.

10. The etching device according to claim 8, characterized in that: The lower end side wall of the air extraction pipe is provided with a plurality of second air extraction holes.

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