CN112635356A

CN112635356A - Wet etching cleaning equipment

Info

Publication number: CN112635356A
Application number: CN202011390854.7A
Authority: CN
Inventors: 袁林涛; 刘宁
Original assignee: Hua Hong Semiconductor Wuxi Co Ltd
Current assignee: Hua Hong Semiconductor Wuxi Co Ltd
Priority date: 2020-12-02
Filing date: 2020-12-02
Publication date: 2021-04-09
Anticipated expiration: 2040-12-02
Also published as: CN112635356B

Abstract

The application discloses wet etching cleaning equipment includes: the inner groove is used for immersing the wafer into the medicament contained in the inner groove for wet etching when the equipment works; the outer groove is arranged outside the inner groove, the bottom groove wall of the inner groove is lower than that of the outer groove, and an opening is formed in the side groove wall between the inner groove and the outer groove; and the circulating system is provided with pipelines which are respectively communicated with the inner tank and the outer tank and are used for refluxing the medicament overflowing from the inner tank to the outer tank to the inner tank when the equipment works. This application sets up the kerve wall that is less than the inside groove through the kerve wall with wet etching cleaning equipment's ectotank, and sets up the opening on the side cell wall between inner trough and the ectotank, and the wafer is after accomplishing the sculpture, and the gravity of usable medicament makes the speed of liquid medicine discharge inside groove accelerate, makes the time difference that the top and the bottom of wafer dip the medicament reduce to the degree of consistency of sculpture has been increased, has improved the etched uniformity of wafer.

Description

Wet etching cleaning equipment

Technical Field

The application relates to the technical field of semiconductor manufacturing, in particular to wet etching cleaning equipment.

Background

In the semiconductor manufacturing industry, wet etching is a process of immersing a wafer in a chemical, etching a thin film to be removed on the wafer, converting the thin film into a soluble compound, and removing the compound, and the equipment for performing the wet etching process is wet etching cleaning equipment.

Referring to fig. 1, there is shown a schematic view of a wet etching cleaning apparatus provided in the related art. As shown in fig. 1, the wet etching cleaning apparatus includes a tank wall 120 and a barrier layer 110 disposed in the tank wall 120, wherein the barrier layer 110 divides a chamber in the tank wall 120 into an outer tank 121 and an inner tank 111. When the apparatus is operated, the inner tank 111 contains the chemical, the wafer 101 is immersed in the chemical from top to bottom, the chemical overflows from the inner tank 111 to the outer tank 121 by means of overflow, and the chemical in the outer tank 121 is returned to the inner tank 111 by a circulation system (not shown in fig. 1).

However, when wet etching is performed by using the cleaning equipment provided in the related art, because the time for immersing the top and the bottom into the chemical is different in the process of feeding and discharging the wafer into and from the chemical, the etching is not uniform, and the higher the etching rate of the chemical is, the larger the difference of the etching amount is, so that the wafer consistency is poor; meanwhile, the heavier particles (such as particles 301 shown in fig. 1) generated during the etching process are deposited at the bottom of the inner tank and are difficult to overflow from the inner tank to the outer tank, so that the particles are likely to adhere to the surface of the wafer during the etching process, thereby forming defects and reducing the reliability of devices integrated on the wafer.

Disclosure of Invention

The application provides a wet etching cleaning equipment, can solve and use the wet etching cleaning equipment who provides among the correlation technique to carry out the wet etching because the etching is inhomogeneous and the problem that uniformity and reliability that particulate matter deposit lead to are relatively poor to the wafer.

In one aspect, an embodiment of the present application provides a wet etching cleaning apparatus, including:

the inner groove is used for immersing the wafer into the medicament contained in the inner groove for wet etching when the equipment works;

the outer tank is arranged outside the inner tank, the bottom tank wall of the outer tank is lower than that of the inner tank, and an opening is formed in the side tank wall between the inner tank and the outer tank;

and the pipeline of the circulating system is respectively communicated with the inner tank and the outer tank and is used for refluxing the medicament overflowing from the inner tank to the outer tank to the inner tank when the wet etching cleaning equipment works.

Optionally, at least two of the openings are disposed on a side groove wall between the inner groove and the outer groove.

Optionally, the outer slots include a first outer slot and a second outer slot, the first outer slot is disposed on one side outside the inner slot, and the second outer slot is disposed on the other side outside the inner slot;

the side slot walls between the inner and outer slots include a first side slot wall between the first outer slot and the inner slot, and a second side slot wall between the second outer slot and the inner slot;

the opening comprises a first opening arranged on the wall of the first side groove and a second opening arranged on the wall of the second side groove.

Optionally, at least two first openings are disposed on the first side groove wall.

Optionally, at least two second openings are disposed on the second side groove wall.

Optionally, the opening is provided in a bottom portion of the side groove wall between the inner groove and the outer groove, the bottom portion being a region below half the height of the side groove wall.

Optionally, a valve is disposed in the opening.

Optionally, when the apparatus is in operation, the valve is closed when the wafer is wet-etched in the chemical;

and when the wafer etching is finished, opening the valve.

Optionally, the circulation system further comprises a filter.

The technical scheme at least comprises the following advantages:

the bottom groove wall of the outer groove of the wet etching cleaning equipment is set to be lower than that of the inner groove, the opening is formed in the side groove wall between the inner groove and the outer groove, after the wafer is etched, the speed of liquid medicine discharged out of the inner groove is accelerated by the aid of the gravity of the liquid medicine, the time difference of the top and the bottom of the wafer immersed in the liquid medicine is reduced, etching uniformity is improved, and wafer etching uniformity is improved.

Drawings

In order to more clearly illustrate the detailed description of the present application or the technical solutions in the prior art, the drawings needed to be used in the detailed description of the present application or the prior art description will be briefly introduced below, and it is obvious that the drawings in the following description are some embodiments of the present application, and other drawings can be obtained by those skilled in the art without creative efforts.

Fig. 1 is a schematic view of a wet etching cleaning apparatus provided in the related art;

FIG. 2 is a schematic diagram of a wet etch cleaning apparatus provided in an exemplary embodiment of the present application;

fig. 3 is a schematic diagram of a wet etching cleaning apparatus according to an exemplary embodiment of the present application.

Detailed Description

The technical solutions in the present application will be described clearly and completely with reference to the accompanying drawings, and it is obvious that the described embodiments are some, but not all embodiments of the present application. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present application.

In the description of the present application, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings, and are only for convenience of description and simplicity of description, and do not indicate or imply that the device or element being referred to must have a particular orientation, be constructed and operated in a particular orientation, and thus, should not be construed as limiting the present application. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance.

In the description of the present application, it is to be noted that, unless otherwise explicitly specified or limited, the terms "mounted," "connected," and "connected" are to be construed broadly, e.g., as meaning either a fixed connection, a removable connection, or an integral connection; the connection can be mechanical connection or electrical connection; the two elements may be directly connected or indirectly connected through an intermediate medium, or may be communicated with each other inside the two elements, or may be wirelessly connected or wired connected. The specific meaning of the above terms in the present application can be understood in a specific case by those of ordinary skill in the art.

In addition, the technical features mentioned in the different embodiments of the present application described below may be combined with each other as long as they do not conflict with each other.

Referring to fig. 2 and 3, which are schematic diagrams illustrating a wet etching cleaning apparatus according to an exemplary embodiment of the present application, as shown in fig. 2 and 3, the apparatus includes:

an inner tank 211 for immersing the wafer 101 in a chemical contained therein for wet etching when the wet etching cleaning apparatus is in operation.

And an outer tub provided outside the inner tub 211, bottom tub walls (bottom tub wall 2221 and bottom tub wall 2222) of the outer tub being lower than the bottom tub wall 212 of the inner tub 211, and openings (opening 2311 and opening 2312) provided on side tub walls (first side tub wall 2101 and second side tub wall 2102) between the inner tub 211 and the outer tub.

Alternatively, the outer slots include a first outer slot 2211 and a second outer slot 2212, the first outer slot 2211 is disposed on one side outside the inner slot 211, the second outer slot 2212 is disposed on the other side outside the inner slot 211, and the side slot walls between the inner slot 211 and the outer slots include a first side slot wall 2101 between the first outer slot 2211 and the inner slot 211 and a second side slot wall 2102 between the second outer slot 2212 and the inner slot 211.

Optionally, at least two openings are provided on the side slot wall between the inner slot 211 and the outer slot. For example, as shown in fig. 3, the first side groove wall 2101 is provided with at least two first openings 2311 (three first openings 2311 are exemplarily illustrated in fig. 3, and may be two openings or more than two openings in practical application), and the second side groove wall 2102 is provided with at least two second openings 2312 (three second openings 2312 are exemplarily illustrated in fig. 3, and may be two openings or more than two openings in practical application).

Alternatively, the openings are provided in the bottom of the side tub walls between the inner tub 211 and the outer tub, which is an area below half the height of the side tub walls. For example, as shown in fig. 2 and 3, if the coordinate of the height of the first side groove wall 2101 in the vertical direction (the vertical direction is a direction perpendicular to the plane of the bottom groove wall) is [0, h ], the value range of the coordinate of the center of the first opening 2311 in the vertical direction is (0, h/2], and if the coordinate of the height of the second side groove wall 2102 in the vertical direction is [0, h ], the value range of the coordinate of the center of the second opening 2312 in the vertical direction is (0, h/2).

And a circulation system, whose pipes are respectively communicated with the inner tank 211 and the outer tank, for returning the chemical overflowing from the inner tank 211 to the outer tank to the inner tank 211 when the wet etching cleaning apparatus is operated.

Illustratively, as shown in fig. 2, the circulation system includes a filter 410, a pump 420, and a heater 430, and pipes of the circulation system are respectively communicated with the inner tank 211 and the outer tank. The filter 410 is arranged to filter heavier particles 301, and cleaning efficiency of the medicament is improved.

To sum up, in this application embodiment, set up the kerve wall that is less than the inner tank through the kerve wall with wet etching cleaning equipment's outer tank, and set up the opening on the side cell wall between inner tank and outer tank, the wafer is after accomplishing the sculpture, and the gravity of usable medicament makes the speed of liquid medicine discharge inside groove accelerate, makes the time difference that the top and the bottom of wafer dip the medicament reduce to the degree of consistency of sculpture has been increased, has improved the etched uniformity of wafer.

Optionally, in this embodiment of the present application, a valve is disposed on the opening. When the wet etching cleaning equipment works and the wafer 101 is subjected to wet etching in the medicament, the valve is closed, and the medicament circulates in an overflow mode; when the wafer 101 is etched, the valve is opened, the chemical is discharged from the inner tank 211 to the outer tank through the opening, the heavier particles 301 deposited at the bottom of the inner tank 211 can be directly discharged to the outer tank through the opening, and then the heavier particles are filtered by the circulating pipeline and enter the inner tank 211, so that the cleaning efficiency of the chemical is improved.

It should be understood that the above examples are only for clarity of illustration and are not intended to limit the embodiments. Other variations and modifications will be apparent to persons skilled in the art in light of the above description. And are neither required nor exhaustive of all embodiments. And obvious variations or modifications of this invention are intended to be covered by the scope of the invention as expressed herein.

Claims

1. A wet etching cleaning apparatus, comprising:

2. The apparatus of claim 1, wherein at least two of the openings are provided in a side slot wall between the inner and outer slots.

3. The apparatus of claim 2, wherein the outer slots include a first outer slot disposed on one side outside the inner slot and a second outer slot disposed on the other side outside the inner slot;

4. The apparatus of claim 3, wherein at least two of the first openings are disposed on the first side slot wall.

5. The apparatus of claim 4, wherein at least two of the second openings are disposed on the second sidewall wall.

6. The apparatus of any one of claims 1 to 5, wherein the openings are provided in the bottom of the side cell walls between the inner and outer cells, the bottom being the area below half the height of the side cell walls.

7. The apparatus of claim 6, wherein a valve is disposed in the opening.

8. The apparatus of claim 7, wherein when the apparatus is in operation, the valve is closed when the wafer is wet etched in the chemical;

and when the wafer etching is finished, opening the valve.

9. The apparatus of claim 8, wherein the circulation system further comprises a filter.