Atomic layer deposition device and atomic layer deposition method
By using the design of the use of reaction chamber and multiple nozzle distributions in the atomic layer deposition device, the uniformity and coverage performance of surface deposition thickness in batch wafer production are achieved, and the uneven thickness and poor coverage performance in the prior art are solved. The problem has improved the chip quality.
Patent Information
- Application Number
- CN202011089730.5
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- Filing Date
- 2020-10-13
- Publication Date
- 2024-12-31
- Estimated Expiration
- 2040-10-13
AI Technical Summary
During semiconductor manufacturing, existing atomic layer deposition technology can easily lead to uneven surface deposition thickness and poor step coverage performance during mass wafer production, affecting wafer quality.
An atomic layer deposition device is designed, including a reaction chamber and a wafer carrier, with multiple nozzles distributed on the side wall or top wall of the reaction chamber, for the introduction of precursors and purification gas into the reaction chamber, ensuring that the surface of multiple wafers is simultaneously A uniform atomic layer film is formed. The process repeats the steps until the target thickness is reached by alternately passing into the first and second precursors and purifying gases to remove excess precursors.
The uniformity of wafer surface deposition thickness and coverage performance are improved, and the wafer quality and production efficiency are improved.
Smart Images
Figure CN114351116B_ABST
Abstract
Description
Technical Field
[0001] The present application belongs to the field of semiconductor manufacturing technology, and specifically relates to an atomic layer deposition device and an atomic layer deposition method. Background Art
[0002] Semiconductor processing during integrated circuit manufacturing typically involves depositing film layers on semiconductor substrates. One method is atomic layer deposition (ALD). Atomic layer deposition typically involves depositing a continuous monolayer of film on a substrate in a reaction chamber below atmospheric pressure. Using typical ALD, film growth on a substrate is achieved by alternately pulsing different deposition precursors onto the substrate surface.
[0003] The ALD method includes introducing a vaporized precursor into a reaction chamber to effectively form a first monolayer film on a substrate placed therein. Thereafter, the introduction of the first vaporized precursor is stopped, and an inert purge gas is introduced to effectively remove the excess first vaporized precursor and reaction byproducts that do not participate in the reaction in the reaction chamber. Subsequently, a second vaporized precursor different from the first vaporized precursor is introduced into the reaction chamber to form a second monolayer film on the first monolayer film. The introduction of the second vaporized precursor is stopped, and an inert purge gas is introduced to effectively remove the excess second vaporized precursor and reaction byproducts that do not participate in the reaction in the reaction chamber. The above process is repeated until a film layer with a desired thickness is formed on the substrate.
[0004] In the prior art, when performing atomic layer deposition on batches of wafers, a furnace-type device is usually used. The wafers are placed on a carrier, and gaseous reactants are sprayed on the sides of the wafers while the carrier is rotated, thereby completing the deposition process of the batch of wafers. In this way, it is easy to cause uneven thickness of the deposition on the wafer surface and poor step coverage, thereby affecting the quality of the wafer. Summary of the invention
[0005] The purpose of this application is to at least solve the problem of uneven surface deposition thickness and poor step coverage performance during wafer batch production. This purpose is achieved by:
[0006] A first aspect of the present application provides an atomic layer deposition device, the atomic layer deposition device comprising:
[0007] Reaction chamber;
[0008] A wafer carrier, the wafer carrier is arranged inside the reaction chamber and is used to carry a plurality of wafers in the same plane;
[0009] A plurality of nozzles are arranged on the side wall or the top wall of the reaction chamber above the wafer carrier, and are used to introduce the first precursor, the second precursor and the purge gas into the reaction chamber.
[0010] Another aspect of the present application further provides an atomic layer deposition method, the atomic layer deposition method comprising the following steps:
[0011] Providing a reaction chamber, laying a plurality of wafers flat on a wafer carrier in the reaction chamber, and keeping the wafer carrier fixed;
[0012] Starting to introduce a first precursor, wherein the first precursor is introduced into the reaction chamber through at least one nozzle among the plurality of nozzles, and forms a first monolayer film on the surface of the wafer;
[0013] Stop introducing the first precursor and start introducing a purge gas, wherein the purge gas is introduced into the reaction chamber through at least one nozzle among the plurality of nozzles to remove the first precursor in the reaction chamber;
[0014] Stopping the introduction of the purge gas and starting to introduce a second precursor, wherein the second precursor is introduced into the reaction chamber through at least one nozzle among the plurality of nozzles and forms a second monolayer film on the surface of the wafer;
[0015] Stop introducing the second precursor and start introducing the purge gas, wherein the purge gas is introduced into the reaction chamber through at least one nozzle among the plurality of nozzles and removes the second precursor in the reaction chamber;
[0016] Repeat the steps of introducing the first precursor, the purge gas and the second precursor until the atomic layer growth reaches the target thickness. BRIEF DESCRIPTION OF THE DRAWINGS
[0017] 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. In addition, the same reference numerals are used throughout the accompanying drawings to represent the same components. Among them:
[0018] Figure 1 A schematic diagram of a portion of the internal structure of an atomic layer deposition device in one embodiment of the present application;
[0019] Figure 2 for Figure 1 AA cross-sectional structure diagram of the atomic layer deposition device;
[0020] Figure 3 for Figure 1 Schematic diagram of the distribution structure of wafers on the wafer carrier.
[0021] The reference numerals in the accompanying drawings represent the following:
[0022] 100: Atomic layer deposition device;
[0023] 10: reaction chamber;
[0024] 20: Wafer carrier;
[0025] 30: nozzle, 31: first nozzle, 32: second nozzle, 33: third nozzle;
[0026] 200: Chip. DETAILED DESCRIPTION
[0027] The exemplary embodiments of the present application will be described in more detail below with reference to the accompanying drawings. Although the exemplary embodiments of the present application are shown in the accompanying drawings, it should be understood that the present application can be implemented in various forms and should not be limited by the embodiments described herein. On the contrary, these embodiments are provided in order to enable a more thorough understanding of the present application and to fully convey the scope of the present application to those skilled in the art.
[0028] It should be understood that the terms used herein are only for the purpose of describing specific example embodiments and are not intended to be limiting. Unless the context clearly indicates otherwise, the singular forms "one", "an" and "said" as used herein may also be meant to include plural forms. The terms "include", "comprise", "contain", and "have" are inclusive, and therefore specify the existence of stated features, steps, operations, elements and / or parts, but do not exclude the existence or addition of one or more other features, steps, operations, elements, parts, and / or combinations thereof. The method steps, processes, and operations described herein are not interpreted as necessarily requiring them to be performed in the specific order described or illustrated, unless the execution order is clearly indicated. It should also be understood that additional or alternative steps may be used.
[0029] Although the terms first, second, third, etc. can be used in the text to describe multiple elements, components, regions, layers and / or sections, these elements, components, regions, layers and / or sections should not be limited by these terms. These terms can only be used to distinguish an element, component, region, layer or section from another region, layer or section. Unless the context clearly indicates, terms such as "first", "second" and other numerical terms do not imply order or sequence when used in the text. Therefore, the first element, component, region, layer or section discussed below can be referred to as the second element, component, region, layer or section without departing from the teaching of the example embodiments.
[0030] For ease of description, spatial relative terms may be used herein to describe the relationship of one element or feature relative to another element or feature as shown in the figure, such as "inside", "outside", "inner side", "outer side", "below", "below", "above", "above", etc. Such spatial relative terms are intended to include different orientations of the device in use or operation in addition to the orientation depicted in the figure. For example, if the device in the figure is turned over, then the elements described as "below other elements or features" or "below other elements or features" will subsequently be oriented as "above other elements or features" or "above other elements or features". Therefore, the example term "below..." can include both upper and lower orientations. The device can be oriented otherwise (rotated 90 degrees or in other directions) and the spatial relative descriptors used in the text are interpreted accordingly.
[0031] Combination Figure 1 and Figure 2 As shown, the atomic layer deposition device 100 of this embodiment includes a reaction chamber 10, a chip carrier 20 and a plurality of nozzles 30. The chip carrier 20 is arranged inside the reaction chamber 10 for carrying a plurality of chips 200 in the same plane. The plurality of nozzles 30 are arranged on the side wall or the top wall of the reaction chamber above the chip carrier 20 for introducing a first precursor, a second precursor and a purification gas into the reaction chamber 10.
[0032] According to the atomic layer deposition device 100 of the present application, multiple chips 200 are simultaneously arranged on the chip carrier 20, and the first precursor and the second precursor are sequentially introduced into the reaction chamber 10 through the nozzle 30, so that atomic layers can be formed on the surfaces of multiple chips 200 at the same time, thereby improving the chip production efficiency. At the same time, there are no obstructions on the surface of the chip 200, which can ensure that the surface of the chip 200 is in full contact with the first precursor and the second precursor, thereby ensuring the uniformity of the deposition thickness and range of the atomic layer and improving the quality of the chip 200.
[0033] Depending on the deposition precursor and substrate materials, ALD has two different self-limiting mechanisms, namely chemical adsorption self-limiting (CS) and sequential reaction self-limiting (RS) processes.
[0034] In the chemical adsorption self-limiting deposition process, the first reaction precursor is input to the surface of the substrate material and is maintained on the surface by chemical adsorption (saturated adsorption). When the second precursor is introduced into the reaction chamber, it will react with the first precursor adsorbed on the surface of the substrate material. A replacement reaction will occur between the two precursors and corresponding by-products will be produced until the first precursor on the surface is completely consumed, the reaction will automatically stop and the required atomic layer will be formed. Therefore, this is a self-limiting process, and this reaction is repeated continuously to form a thin film.
[0035] Unlike the chemical adsorption self-limiting process, the sequential reaction self-limiting atomic layer deposition process is driven by the chemical reaction between the active precursor substance and the active substrate material surface. The deposited film obtained in this way is formed by the chemical reaction between the precursor and the substrate material. The process first activates the substrate material surface with an activator, and then the first precursor injected reacts on the activated substrate material surface to form an adsorbed intermediate. When the second precursor is injected into the reactor, it will react with the above-mentioned adsorbed intermediate and generate a deposited atomic layer.
[0036] The plurality of nozzles 30 of this embodiment include a plurality of first nozzles 31, a plurality of second nozzles 32, and a plurality of third nozzles 33. The plurality of first nozzles 31 are used to introduce the first precursor into the reaction chamber 10, the plurality of second nozzles 32 are used to introduce the second precursor into the reaction chamber 10, and the plurality of third nozzles 33 are used to introduce the purge gas into the reaction chamber 10.
[0037] The first precursor is introduced into the reaction chamber 10 through the first nozzle 31, and the first precursor is adsorbed on the surface of the wafer 200 due to its own characteristics. Then, the purge gas is introduced into the reaction chamber 10 through the third nozzle 33 to completely drive out the first precursor that is not adsorbed on the surface of the wafer 200 from the reaction chamber 10. Then, the second precursor is introduced into the reaction chamber 10 through the second nozzle 32, and the second precursor reacts with the first precursor attached to the surface of the wafer 200 to form an atomic layer. The above steps are repeated until an atomic layer of a desired thickness is obtained.
[0038] In order to ensure the formation process of the atomic layer and enable the purification gas to effectively remove the first precursor and the second precursor, the second nozzle 32, the third nozzle 33 and the first nozzle 31 are arranged from top to bottom along the side wall of the reaction chamber 10.
[0039] like Figure 3 As shown, the reaction chamber 10 of this embodiment is a rectangular structure, and the wafer carrier 20 inside it is also a rectangular structure, so as to set the distance between the edge of the wafer carrier 20 and the inner wall of the reaction chamber 10. The number of wafers 200 on the wafer carrier 20 is set to 25, which just meets the number of wafers 200 in the same box, thereby ensuring the uniformity of the coverage thickness of the wafers 200 in the same box. The 25 wafers are arranged in 5 rows with equal intervals, and any row includes 5 wafers arranged with equal intervals.
[0040] In the present embodiment, a plurality of first nozzles 31 are relatively arranged on the opposite side walls in the length direction of the reaction chamber 10, and the spraying distance of the first nozzle 31 is at least the shortest straight-line distance from the inner wall of the reaction chamber 10 to the center of the chip carrier 20, thereby ensuring that the first precursor sprayed by the first nozzle 31 can fully and effectively cover the multiple chips 200 on the chip carrier 20, thereby ensuring that the atomic layer formed later has uniform thickness and coverage.
[0041] In the present embodiment, the opposite side walls in the length direction of the reaction chamber 10 are respectively provided with a plurality of second nozzles 32 and a plurality of third nozzles 33. The spraying distance of the second nozzle 32 and the third nozzle 33 is also at least the shortest straight-line distance from the inner wall of the reaction chamber 10 to the center of the chip carrier 20, thereby ensuring that the second precursor can fully and effectively cover the multiple chips 200 on the chip carrier 20, and the purification gas can effectively remove the first precursor, thereby ensuring that the atomic layer formed later has uniform thickness and coverage.
[0042] In other embodiments of the present application, the first nozzle 31 , the second nozzle 32 , and the third nozzle 33 may be disposed on the four inner walls of the reaction chamber 10 , so as to further ensure that the formed atomic layer has uniform thickness and coverage.
[0043] In other embodiments of the present application, the multiple nozzles 30 also include multiple fourth nozzles (consistent with the setting form of the first nozzle 31, not shown in the figure), and the multiple fourth nozzles are used to introduce intermediate gas into the reaction chamber 10. The fourth nozzles are arranged below the first nozzle 31 along the side wall of the reaction chamber 10.
[0044] When the first precursor is insufficient to cover the base material by its own characteristics, an intermediate gas is introduced into the reaction chamber 10 through the fourth nozzle. First, the intermediate gas is introduced to activate the surface of the wafer 200, and then the first precursor is introduced to react with the surface of the activated wafer 200 to form an adsorbed intermediate, and then the second precursor is introduced to react with the adsorbed intermediate to form an atomic layer.
[0045] In other embodiments of the present application, the intermediate gas may be firstly sprayed into the reaction chamber 10 through the second nozzle 32 , and then the first precursor and the second precursor may be sprayed in sequence through the first nozzle 31 , so that atomic layer deposition can also be achieved.
[0046] The atomic layer deposition apparatus 100 of the embodiment of the present application further includes a heating unit, the heating portion of which is disposed inside or outside the wafer carrier 20, and is used to control the temperature in the reaction chamber 10, thereby satisfying the reaction conditions of the first precursor and the second precursor. The heating unit may be a controllable heating coil.
[0047] The present application also proposes an atomic layer deposition method. The atomic layer deposition method of this embodiment includes the following steps:
[0048] A reaction chamber 10 is provided, and a plurality of wafers 200 are laid flat on a wafer carrier 20 in the reaction chamber 10, and the wafer carrier 20 is kept fixed. The number of wafers 200 on the wafer carrier 20 is set to 25, and the 25 wafers 200 are arranged in 5 rows arranged at equal intervals, and any row includes 5 wafers 200 arranged at equal intervals.
[0049] The first precursor begins to be introduced into the reaction chamber 10 through a plurality of first nozzles 31 , and forms a first single-layer film on the surface of the wafer 200 .
[0050] The introduction of the first precursor is stopped, and the introduction of the purge gas is started. The purge gas is introduced into the reaction chamber 10 through the plurality of third nozzles 33 , and removes the first precursor in the reaction chamber 10 .
[0051] The purge gas is stopped and the second precursor is started to be introduced. The second precursor is introduced into the reaction chamber 10 through a plurality of second nozzles 32 and forms a second single-layer film on the surface of the wafer 200 .
[0052] The introduction of the second precursor is stopped, and the introduction of the purge gas is started. The purge gas is introduced into the reaction chamber 10 through the plurality of third nozzles 33 , and the second precursor in the reaction chamber 10 is removed.
[0053] The steps of introducing the first precursor, the purge gas and the second precursor are repeated until the atomic layer growth reaches the target thickness.
[0054] Furthermore, when the first precursor is insufficient to cover the wafer 200 by its own characteristics, an intermediate gas is introduced into the reaction chamber 10 to activate the surface of the wafer 200. Then, the ventilation steps in the above embodiments are sequentially performed to achieve atomic layer deposition.
[0055] The above is only a preferred specific implementation of the present application, but the protection scope of the present application is not limited thereto. Any changes or substitutions that can be easily thought of by a person skilled in the art within the technical scope disclosed in the present application should be included in the protection scope of the present application. Therefore, the protection scope of the present application should be based on the protection scope of the claims.
Claims
1. An atomic layer deposition device, characterized in that: include: Reaction chamber; A wafer carrier, the wafer carrier is arranged inside the reaction chamber and is used to carry a plurality of wafers in the same plane; A plurality of nozzles, wherein the plurality of nozzles are disposed on the side wall or the top wall of the reaction chamber above the wafer carrier, and are used to introduce a first precursor, a second precursor and a purge gas into the reaction chamber, wherein: The plurality of nozzles comprises: A plurality of first nozzles, wherein the plurality of first nozzles are used to introduce the first precursor into the reaction chamber; A plurality of second nozzles, wherein the plurality of second nozzles are used to introduce the second precursor into the reaction chamber; A plurality of third nozzles, wherein the plurality of third nozzles are used to introduce the purification gas into the reaction chamber; The second nozzle, the third nozzle and the first nozzle are arranged at intervals from top to bottom along the side wall of the reaction chamber; The plurality of first nozzles are disposed at least on a pair of oppositely disposed side walls of the reaction chamber; The plurality of the second nozzles are disposed at least on a pair of oppositely disposed side walls of the reaction chamber; The plurality of third nozzles are disposed on at least a pair of oppositely disposed side walls of the reaction chamber.
2. The atomic layer deposition device according to claim 1, characterized in that: The plurality of nozzles further include a plurality of fourth nozzles, which are used to introduce intermediate gas into the reaction chamber, and the fourth nozzles are arranged below the first nozzles along the side wall of the reaction chamber.
3. The atomic layer deposition device according to claim 1, characterized in that: The atomic layer deposition apparatus further includes a heating unit, wherein the heating unit is partially disposed on an inner wall or an outer wall of the carrier.
4. The atomic layer deposition device according to claim 1, characterized in that: The wafer carrier is used to carry at least 25 wafers.
5. An atomic layer deposition method, using the atomic layer deposition apparatus as claimed in claim 1, characterized in that: The following steps are involved: Providing a reaction chamber, laying a plurality of wafers flat on a wafer carrier in the reaction chamber, and keeping the wafer carrier fixed; Starting to introduce a first precursor, wherein the first precursor is introduced into the reaction chamber through at least one nozzle among the plurality of nozzles, and forms a first monolayer film on the surface of the wafer; Stop introducing the first precursor and start introducing a purge gas, wherein the purge gas is introduced into the reaction chamber through at least one nozzle among the plurality of nozzles to remove the first precursor in the reaction chamber; Stopping the introduction of the purge gas and starting to introduce a second precursor, wherein the second precursor is introduced into the reaction chamber through at least one nozzle among the plurality of nozzles and forms a second monolayer film on the surface of the wafer; Stop introducing the second precursor and start introducing the purge gas, wherein the purge gas is introduced into the reaction chamber through at least one nozzle among the plurality of nozzles and removes the second precursor in the reaction chamber; Repeat the steps of introducing the first precursor, the purge gas and the second precursor until the atomic layer growth reaches the target thickness.
6. The atomic layer deposition method according to claim 5, characterized in that: The step of introducing the first precursor also includes the following steps: An intermediate gas is introduced into the reaction chamber so that the intermediate gas activates the surface of the wafer.
7. The atomic layer deposition method according to claim 5, characterized in that: The plurality of wafers are laid out on the wafer carrier in the form of five rows arranged at equal intervals, and the number of the wafers in any row is set to five, so that the five wafers in any row are arranged at equal intervals.