Wafer wet etching device and etching method

Abstract

The embodiment of the invention discloses a wafer wet etching device and an etching method, the wafer wet etching device comprises a barrel body, a driving assembly and a bearing assembly, the bearing assembly comprises a plurality of stand columns, and a clamping groove is formed in each stand column. According to the wafer wet etching device provided by the embodiment of the invention, in the use process, the wafer can be clamped on the plurality of stand columns through the clamping grooves, then the bearing assembly and the wafer are placed in the barrel body, the corrosive liquid in the barrel body is driven to flow through the driving assembly, and the corrosive liquid can perform wet etching on the wafer. The mode of driving the corrosive liquid to flow through the driving assembly is used for replacing a traditional mode of manually rotating the wafer, on one hand, the flow speed of the corrosive liquid is controllable, and the wet etching efficiency can be improved; and on the other hand, the consistency and uniformity of wet etching can be guaranteed.

Description

Technical Field

[0001] The embodiments of the present application relate to the field of semiconductor chip manufacturing technology, and in particular to a wafer wet etching device and etching method. Background Art

[0002] With the development of the semiconductor industry, the pursuit of high performance and high reliability is often accompanied by the improvement of material and structural difference design and process requirements. As an important part of the semiconductor process, the corrosion process is related to the performance, reliability and yield of semiconductor chips. The performance bandwidth and reliability of photodetectors and APDs in the semiconductor subdivision field are directly related to the corrosion process. Mature and stable corrosion equipment and processes can not only meet the performance and reliability requirements but also improve the product yield. In traditional technologies, wet corrosion mostly uses non-standard flower baskets to manually rotate the wafers in the corrosion liquid or add axial rotation and axial swing corrosion. The manual rotation speed is uncontrollable and the consistency and uniformity cannot be guaranteed; adding axial rotation or swing corrosion requires a large space, a large amount of corrosion liquid, and the corrosion liquid has a large impact on the wafer and is easy to crack. Axial rotation or swing corrosion cannot be sealed for volatile corrosion liquids, and the corrosion liquid rate decreases quickly. For some layers with different materials and multi-layer wafer structures, it is necessary to observe the color to judge which layer is easily corroded. This makes it impossible for wet corrosion to ensure high uniformity and consistency, resulting in low yield of some table processes. Summary of the invention

[0003] The present invention aims to solve at least one of the technical problems existing in the prior art or related art.

[0004] To this end, a first aspect of the present invention provides a wafer wet etching device.

[0005] A second aspect of the present invention provides an etching method.

[0006] In view of this, according to a first aspect of an embodiment of the present application, a wafer wet etching device is proposed, comprising:

[0007] A barrel body, wherein the barrel body is used to carry the corrosive liquid;

[0008] A driving component, the driving component is used to drive the corrosive liquid to flow;

[0009] The bearing assembly is used to be arranged in the barrel body. The bearing assembly includes a plurality of columns. A slot is formed on each of the columns. The wafer is positioned in the barrel body through the slot and the plurality of columns.

[0010] In a feasible implementation manner, the bearing assembly includes:

[0011] A first fixing seat, wherein a plurality of assembly ports and at least one card interface are formed on the first fixing seat;

[0012] At least one of the plurality of columns is detachably connected to the first fixing seat through the card interface, and the other columns are connected to the first fixing seat through the assembly port;

[0013] A second fixing seat, the other end of the column is connected to the second fixing seat, and the second fixing seat is used to be arranged in the barrel body.

[0014] In a feasible implementation manner, a step surface and a hollow portion are formed on the second fixing seat.

[0015] In a feasible implementation manner, each of the columns is formed with a plurality of the slots along the height direction.

[0016] In a feasible implementation manner, on each of the pillars, the density of the groove distribution gradually increases in a direction closer to the barrel body.

[0017] In a feasible implementation manner, the top surface of the slot is an inclined surface.

[0018] In a feasible implementation, the driving component includes:

[0019] A magnetic motor, wherein the magnetic motor is arranged in the compartment of the barrel;

[0020] The magnetic rotor is arranged in the barrel body, and the magnetic motor is used to drive the magnetic rotor to rotate.

[0021] In a feasible implementation manner, the wafer wet etching device further includes:

[0022] A positioning post is arranged on the barrel body or the bearing assembly. A through hole is formed on the magnetic rotor, and the positioning post passes through the through hole.

[0023] In a feasible implementation manner, the inner diameter of the barrel body gradually increases in a direction from a high point to a low point of the barrel body.

[0024] According to a second aspect of an embodiment of the present application, an etching method is proposed, which is applied to a wafer wet etching device as described in any of the above technical solutions. The etching method includes:

[0025] Connecting the wafer to the column through the slot;

[0026] The bearing assembly is arranged in the barrel;

[0027] The driving component drives the corrosive liquid in the barrel to flow, and the corrosive liquid is used to etch the wafer.

[0028] Compared with the prior art, the present invention has at least the following beneficial effects:

[0029] The wafer wet etching device provided in the embodiment of the present application includes a barrel, a driving component and a supporting component. The supporting component includes a plurality of columns, each of which has a card slot formed thereon. Based on this, in the use of the wafer wet etching device provided in the embodiment of the present application, the wafer can be first connected to the plurality of columns through the card slot, and then the supporting component and the wafer are placed in the barrel, and the etching liquid in the barrel is driven to flow by the driving component, so that the etching liquid can wet-etch the wafer. The present application replaces the traditional method of manually rotating the wafer by driving the etching liquid to flow through the driving component. On the one hand, the controllable flow rate of the etching liquid can improve the efficiency of wet etching; on the other hand, it can ensure the consistency and uniformity of wet etching. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Various other advantages and benefits will become apparent to those of ordinary skill in the art by reading the detailed description of the preferred embodiments below. The accompanying drawings are only for the purpose of illustrating the preferred embodiments and are not to be considered as limiting the present application. Also, the same reference symbols are used throughout the accompanying drawings to represent the same components. In the accompanying drawings:

[0031] Figure 1 A schematic structural diagram of a wafer wet etching device according to an embodiment of the present application;

[0032] Figure 2 A schematic structural diagram of a magnetic rotor of a drive assembly of a wafer wet etching device according to an embodiment of the present application;

[0033] Figure 3 A schematic structural diagram of a second fixing base of a wafer wet etching device according to an embodiment of the present application;

[0034] Figure 4 A schematic structural diagram of a column of a wafer wet etching device according to an embodiment of the present application;

[0035] Figure 5 A schematic structural diagram of another column of a wafer wet etching device according to an embodiment of the present application;

[0036] Figure 6 A schematic flowchart of the etching method according to an embodiment of the present application.

[0037] in, Figures 1 to 5 The corresponding relationship between the reference numerals and the component names is as follows:

[0038] 110 barrel body, 120 driving assembly, 130 bearing assembly, 140 positioning column;

[0039] 121 is a magnetic rotor, 122 is a through hole, 131 is a column, 132 is a slot, 133 is a first fixing seat, 134 is a second fixing seat, 135 is a step surface, and 136 is a hollow portion. DETAILED DESCRIPTION

[0040] In order to better understand the above-mentioned technical scheme, the technical scheme of the embodiments of the present application is described in detail below through the accompanying drawings and specific embodiments. It should be understood that the embodiments of the present application and the specific features in the embodiments are detailed descriptions of the technical scheme of the embodiments of the present application, rather than limitations on the technical scheme of the present application. In the absence of conflict, the embodiments of the present application and the technical features in the embodiments may be combined with each other.

[0041] like Figures 1 to 5 As shown, according to the first aspect of an embodiment of the present application, a wafer wet etching device is proposed, including: a barrel body 110, the barrel body 110 is used to carry etching liquid; a driving component 120, the driving component 120 is used to drive the etching liquid to flow; a supporting component 130, the supporting component 130 is used to be arranged in the barrel body 110, the supporting component 130 includes a plurality of columns 131, each column 131 is formed with a slot 132, and the wafer is positioned in the barrel body 110 through the slot 132 and the plurality of columns 131.

[0042] The wafer wet etching device provided in the embodiment of the present application includes a barrel 110, a driving component 120 and a bearing component 130, and the bearing component 130 includes a plurality of columns 131, and each column 131 is formed with a card slot 132. Based on this, in the use of the wafer wet etching device provided by the embodiment of the present application, the wafer can be firstly connected to the plurality of columns 131 through the card slot 132, and then the bearing component 130 is connected to the wafer to prevent it from being in the barrel 110, and the etching liquid in the barrel 110 is driven to flow by the driving component 120, and the etching liquid can wet-etch the wafer. The present application uses the method of driving the etching liquid to flow by the driving component 120 to replace the traditional method of manually rotating the wafer. On the one hand, the controllable flow rate of the etching liquid can improve the efficiency of wet etching; on the other hand, it can ensure the consistency and uniformity of wet etching, which is suitable for batch production of wafer etching.

[0043] like Figures 1 to 5As shown, in a feasible embodiment, the supporting assembly 130 includes: a first fixed seat 133, on which a plurality of assembly ports and at least one card interface are formed; wherein at least one column 131 among a plurality of columns 131 is detachably connected to the first fixed seat 133 via the card interface, and the other columns 131 are connected to the first fixed seat 133 via the assembly port; and a second fixed seat 134, wherein the other end of the column 131 is connected to the second fixed seat 134, and the second fixed seat 134 is used to be arranged in the barrel body 110.

[0044] In this technical solution, a style of a bearing assembly 130 is further provided. In addition to the column 131, the bearing assembly 130 may also include a first fixing seat 133 and a second fixing seat 134. The first fixing seat 133 may be arranged at the top, and the second fixing seat 134 may be arranged at the bottom. Furthermore, at least one of the columns 131 is detachably connected to the first fixing seat 133 through a card interface, and the other columns 131 are connected to the first fixing seat 133 through the assembly port. Based on this, during use, In this case, some of the columns 131 can be connected to the assembly port first. In this case, the multiple columns 131 can open a relatively large space, and the wafer can be set in the space enclosed by the multiple columns 131, and then the wafer is set in the card slots 132 in the multiple columns 131, and finally the other columns 131 are set at the card interface. The card slots 132 on these columns 131 are also carded with the wafer, so that the wafer can be fixed, which can prevent the wafer from shaking during wet etching and affecting the etching effect.

[0045] In some examples, there may be four pillars 131, and one of the four pillars 131 is connected to the card interface, and the other pillars 131 are connected to the assembly port. Such a setting can not only fix the wafer, but also minimize the number of pillars 131. The four pillars 131 form four support points around the circumference of the wafer, so that each area of ​​the wafer can be corroded by the corrosive liquid, avoiding the problem that the clamping area is too large and part of the wafer cannot be corroded, and at the same time avoiding the problem that the wafer is not fixed in the liquid and easily floats and collides during the rotation process, causing fragmentation.

[0046] In some examples, an arc-shaped handle may be provided on the first fixing seat 133 to facilitate the user to take and place the wafer and the carrier assembly 130, making the use of the wafer wet etching device safer. It is understandable that in order to facilitate the user to hold the carrier assembly 130, the handle may also be arranged on both sides of the first fixing seat 133.

[0047] like Figures 1 to 5 As shown, in a feasible implementation manner, a step surface 135 and a hollow portion 136 are formed on the second fixing seat 134 .

[0048] In this technical solution, a style of a second fixed seat 134 is further provided, and a step surface 135 and a hollow portion 136 are formed on the second fixed seat 134. Such a configuration can ensure the fluidity of the liquid when the driving component 120 is turned on, can avoid contact between the driving component 120 and the wafer, and ensure the wet corrosion efficiency and etching efficiency.

[0049] like Figures 1 to 5 As shown, in a feasible implementation manner, each column 131 is formed with a plurality of slots 132 along the height direction.

[0050] In this technical solution, a plurality of slots 132 can be formed on each column 131, based on which a plurality of wafers can be fixed by the plurality of columns 131, and the plurality of wafers can be stacked along the height direction of the columns 131, which can further improve the etching efficiency of the wafer wet etching device.

[0051] In a feasible implementation, on each column 131 , the density of the grooves 132 gradually increases in a direction closer to the barrel body 110 .

[0052] In this technical solution, when a plurality of slots 132 are formed on the column 131, a distribution trend of the slots 132 is further provided. On each column 131, the density of the slots 132 gradually increases in the direction close to the barrel body 110, that is, the closer to the top of the column 131, the longer the distance between two adjacent slots 132, and conversely, the closer to the bottom of the column 131, the shorter the distance between two adjacent slots 132. This arrangement is based on the consideration that when the etching liquid is driven to flow by the driving assembly 120, the liquid flow rate at the bottom of the barrel body 110 may be higher. Through this arrangement of the slots 132, the etching efficiency of the wafer at the top of the barrel body 110 can be the same as or close to that of the wafer at the bottom, thereby further ensuring the consistency of etching.

[0053] In a feasible implementation manner, the top surface of the slot 132 is an inclined surface.

[0054] In this technical solution, a style of the slot 132 is further provided, and the top surface of the slot 132 is a slope, based on which the contact area between the slot 132 and the wafer can be reduced, and while preventing the wafer from loosening, the obstruction of the wafer caused by the setting of the slot 132 can be minimized, so that more areas of the wafer can be etched and the etching effect can be improved.

[0055] In some examples, the bottom surface of the slot 132 may be a plane, so that the slot 132 can better support the wafer and reduce the probability of the wafer slipping when being loaded.

[0056] In a feasible implementation, the driving assembly 120 includes: a magnetic motor, which is disposed in a partition of the barrel body 110; and a magnetic rotor 121, which is disposed in the barrel body 110, and the magnetic motor is used to drive the magnetic rotor 121 to rotate.

[0057] In this technical solution, a style of a driving component 120 is further provided. The driving component 120 may include a magnetic motor and a magnetic rotor 121. The magnetic motor is arranged in the partition of the barrel body 110, and the magnetic rotor 121 is arranged in the barrel body 110. Based on this, the magnetic motor can drive the magnetic rotor 121 to rotate in a non-contact manner, and then the magnetic rotor 121 can drive the liquid stored in the barrel body 110 to rotate. Based on this, the service life of the driving component 120 can be guaranteed, and at the same time, the contamination of the corrosive liquid due to the setting of the driving component 120 can be avoided, thereby ensuring the sealing of the corrosive liquid.

[0058] In this technical solution, the magnetic rotor 121 is used in combination with the step surface 135 and the hollow portion 136 on the second fixed seat 134. The other parts below the step surface 135 except the support and positioning area are opened to form the hollow portion 136 to ensure the fluidity of the liquid when the magnetic rotor 121 rotates. The rotation of the magnetic rotor 121 drives the liquid to rotate instead of the manual rotation of the flower basket corrosion, which increases the fluidity of the etching liquid. Not only the speed is controllable, but also the consistency and uniformity are improved. The use of the magnetic rotor 121 to drive the liquid flow replaces the traditional technology of rotating the flower basket to drive the liquid corrosion. Because the liquid does not rotate when the wafer itself rotates, the color change of the wafer corrosion surface can be observed during the corrosion process to control the stop of the corrosion, which can prevent the corrosion of the etching liquid from causing excessive corrosion, and is more conducive to the judgment of the corrosion depth.

[0059] In a feasible implementation, the wafer wet etching device further includes: a positioning post 140 , which is disposed on the barrel 110 or the bearing assembly 130 , and a through hole 122 is formed on the magnetic rotor 121 , and the positioning post 140 passes through the through hole 122 .

[0060] In this technical solution, the wafer wet etching device may further include a positioning column 140, and a through hole 122 may be formed on the magnetic rotor 121. The positioning column 140 may pass through the through hole 122 to position the magnetic rotor 121, thereby making the flow of the etching liquid more uniform and improving the etching effect.

[0061] In a feasible implementation manner, the inner diameter of the barrel body 110 gradually increases in a direction from a high point to a low point of the barrel body 110 .

[0062] In this technical solution, a style of the barrel body 110 is further provided. In the direction from the high point to the low point of the barrel body 110, the inner diameter of the barrel body 110 gradually increases, that is, it tends to be smaller at the top and larger at the bottom in the height direction of the barrel body 110. Considering that when the etching liquid is driven to flow by the driving component 120, the liquid flow rate at the bottom of the barrel body 110 may be higher, through this barrel body 110 structural design method, the etching efficiency of the wafer at the top of the barrel body 110 can be the same or close to the etching efficiency of the wafer at the bottom, which can further ensure the consistency of corrosion.

[0063] In some examples, the wafer wet etching device may further include a cover, which may be disposed on the barrel 110. The cover may seal the carrier assembly 130 to improve the sealing effect.

[0064] In some examples, a pouring portion may be formed on the barrel body 110 , and the pouring portion is used to pour the corrosive liquid in the barrel body.

[0065] like Figure 6 As shown, according to the second aspect of the embodiment of the present application, an etching method is proposed, which is applied to a wafer wet etching device as in any of the above technical solutions, and the etching method includes:

[0066] Step 201: Connect the wafer to the column through the slot;

[0067] Step 202: placing the bearing assembly in the barrel;

[0068] Step 203: driving the etching liquid in the barrel to flow through the driving component, and etching the wafer with the etching liquid.

[0069] The etching method provided in the embodiment of the present application is applied to a wafer wet etching device such as any of the above-mentioned technical solutions, so the etching method has all the beneficial effects of the wafer wet etching device of the above-mentioned technical solutions.

[0070] In some examples, the etching method may specifically include the following steps:

[0071] 1. Apply photoresist on the back of the wafer and cure it on a 120°C hot plate for 3 minutes to protect the back of the wafer from corrosion that affects the corrosion rate.

[0072] 2. Take out the magnetic rotor and place it on the positioning column, and place the wafers on the columns of the wafer wet etching device one by one.

[0073] 3. Pour the prepared bromine water etching solution into the barrel and place it on the magnetic stirrer.

[0074] 4. Place the carrier assembly containing the wafer in the etching solution, start the timing and turn on the magnetic stirrer to adjust the speed to 220 rpm.

[0075] 5. Observe the color change of the wafer surface during the corrosion process. After the first layer of Inp is corroded and the color changes, the second layer of InGaAsP+InGaAs changes, the third layer of InAlAs changes, and the fourth layer of Inp changes. The corrosion process is 8-10 minutes in total. Take out the carrier component and rinse it with deionized water.

[0076] 6. Take out the wafer and use a step profiler to test the corrosion depth.

[0077] In the present invention, the terms "first", "second", and "third" are used for descriptive purposes only and should not be understood as indicating or implying relative importance; the term "plurality" refers to two or more, unless otherwise clearly defined. The terms "installed", "connected", "connected", "fixed", etc. should be understood in a broad sense. For example, "connected" can be a fixed connection, a detachable connection, or an integral connection; "connected" can be a direct connection or an indirect connection through an intermediate medium. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0078] In the description of the present invention, it is necessary to understand that the directions or positional relationships indicated by terms such as “upper”, “lower”, “left”, “right”, “front” and “back” are based on the directions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or unit referred to must have a specific direction, be constructed and operated in a specific orientation, and therefore, cannot be understood as a limitation on the present invention.

[0079] In the description of this specification, the description of the terms "one embodiment", "some embodiments", "specific embodiments", etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner.

[0080] The above are only preferred embodiments of the present invention and are not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A wafer wet etching device, It is characterized in that include: A barrel body, wherein the barrel body is used to carry the corrosive liquid; A driving component, the driving component is used to drive the corrosive liquid to flow; The bearing assembly is used to be arranged in the barrel body. The bearing assembly includes a plurality of columns. A slot is formed on each of the columns. The wafer is positioned in the barrel body through the slot and the plurality of columns.

2. The wafer wet etching device according to claim 1, It is characterized in that The bearing assembly comprises: A first fixing seat, wherein a plurality of assembly ports and at least one card interface are formed on the first fixing seat; At least one of the plurality of columns is detachably connected to the first fixing seat through the card interface, and the other columns are connected to the first fixing seat through the assembly port; A second fixing seat, the other end of the column is connected to the second fixing seat, and the second fixing seat is used to be arranged in the barrel body.

3. The wafer wet etching device according to claim 2, It is characterized in that A step surface and a hollow portion are formed on the second fixing seat.

4. The wafer wet etching device according to claim 1, It is characterized in that Each of the columns is formed with a plurality of the slots along the height direction.

5. The wafer wet etching device according to claim 4, It is characterized in that On each of the upright posts, the density of the slots gradually increases in a direction closer to the barrel body.

6. The wafer wet etching device according to claim 1, It is characterized in that The top surface of the slot is an inclined surface.

7. The wafer wet etching device according to any one of claims 1 to 6, It is characterized in that The drive components include: A magnetic motor, wherein the magnetic motor is arranged in the partition of the barrel body; The magnetic rotor is arranged in the barrel body, and the magnetic motor is used to drive the magnetic rotor to rotate.

8. The wafer wet etching device according to claim 7, It is characterized in that Also includes: A positioning post is arranged on the barrel body or the bearing assembly. A through hole is formed on the magnetic rotor, and the positioning post passes through the through hole.

9. The wafer wet etching device according to any one of claims 1 to 6, It is characterized in that The inner diameter of the barrel body gradually increases in a direction from a high point to a low point of the barrel body.

10. An etching method, It is characterized in that Applied to the wafer wet etching device according to any one of claims 1 to 9, the etching method comprises: Connecting the wafer to the column through the slot; The bearing assembly is arranged in the barrel; The driving component drives the etching liquid in the barrel to flow, and the etching liquid is used to etch the wafer.

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