CN-121992363-A - Atomic layer deposition equipment and method for integrated in-situ switchable mask plate

CN121992363ACN 121992363 ACN121992363 ACN 121992363ACN-121992363-A

Abstract

The invention discloses atomic layer deposition equipment and method for an integrated in-situ switchable mask plate, and belongs to the technical field of semiconductor micro-nano manufacturing. The equipment comprises a deposition cavity, a multi-source precursor conveying system, a built-in mask plate library and switching mechanism, a substrate pose adjusting device and a control system. The mask plate library and the switching mechanism are integrated in a vacuum environment, the mask plate library and the switching mechanism have the functions of multi-station mask plate bearing and high-precision positioning, and the substrate pose adjusting device is matched with the micro-distance adjusting unit, so that the mask plate and the substrate can be switched between a non-contact switching state and a close fitting deposition state. Under the condition of maintaining high vacuum, the invention realizes the automatic replacement of different pattern mask plates and the alternate deposition of multi-layer precursor pulses through program control, effectively solves the problems of interface pollution and alignment deviation caused by frequent vacuum breaking in the traditional patterning ALD process, and is particularly suitable for the preparation of high-quality two-dimensional material Van der Waals heterostructures and three-dimensional micro-nano structures.

Inventors

LIU LEI
WANG DEYI
LU JINGQI

Assignees

东南大学
西班牙马德里高等材料研究院高性能纳米材料研究中心

Dates

Publication Date: 20260508
Application Date: 20260203

Claims (10)

1. An atomic layer deposition apparatus integrating an in-situ switchable mask, comprising: The middle part of the upper part of the deposition cavity is provided with a central shaft, and a heating sample table with a heating function is arranged in the deposition cavity to define a vacuum reaction chamber for film deposition; the multi-source precursor conveying system is communicated with the deposition cavity and is used for providing and conveying two or more precursor sources and purge gases in a pulse mode; the built-in mask plate library and the switching mechanism are arranged in the deposition cavity and comprise mask bearing frames used for bearing a plurality of mask plates with different patterns and a driving device for driving the mask bearing frames to move so as to select a target mask plate; The micro-distance adjusting unit is arranged on the substrate bearing table or the mask bearing frame and is used for adjusting the relative distance between the target mask plate and the substrate in the vertical direction so as to realize deposition gap control and lamination; The control system is electrically connected with the multi-source precursor conveying system, the driving device and the micro-distance adjusting unit and is used for cooperatively controlling precursor conveying, mask plate switching, deposition gaps and process temperature.
2. The apparatus of claim 1, wherein the carrier of the built-in reticle library and switching mechanism is of a disc type structure rotatable about its center axis, the reticles are circumferentially distributed along the turntable, the drive means is a stepper motor or a servo motor, and power is transferred to the carrier within the vacuum chamber via a magnetic coupler or a vacuum feed-through.
3. The apparatus according to claim 1 or 2, wherein a macro adjustment unit is provided between the heating sample stage and the mask plate carrier plate for precisely controlling a distance between a lower surface of the mask plate and an upper surface of the substrate, the distance being switchable between a bonding state and a predetermined micro distance.
4. The apparatus of claim 3, wherein the macro adjustment unit comprises a piezoceramic actuator or a precision stepper lead screw lifting mechanism integrated on the support of the heated sample stage or reticle carrier plate that controls a reticle to substrate spacing pattern comprising: The switching mode is that the spacing is 1-5mm and is used for replacing and moving the mask plate; deposition mode, spacing 0-100 μm or zero distance contact, for preventing lateral diffusion of precursor.
5. The apparatus of claim 1, further comprising an in-situ alignment monitoring system comprising an optical inspection window and a CCD vision module disposed outside the deposition chamber for precise positioning between the pattern on the reticle and a pre-set mark or existing pattern on the substrate.
6. The apparatus of claim 1, wherein the multi-source precursor delivery system comprises at least two separate precursor source bottles and corresponding constant temperature heating jackets, piping, mass flow controllers, and high-speed pneumatic valves, the precursor sources comprising one or more of metal halides, organometallic compounds, water, or chalcogenides.
7. An atomic layer deposition method based on an apparatus according to any one of claims 1 to 6, comprising the steps of: S1, mounting a substrate on a substrate bearing table in a deposition cavity, vacuumizing the deposition cavity and heating the substrate to a preset deposition temperature; S2, driving the mask plate library and the switching mechanism through the control system, and moving and positioning the selected first mask plate to the position right above the substrate; s3, reducing the distance between the mask plate and the substrate through a micro-distance adjusting unit, and entering a deposition mode; s4, pulse-feeding a first precursor into the deposition cavity through a multi-source precursor conveying system to enable self-limiting chemical adsorption to occur on the surface of the non-shielding area of the substrate; S5, introducing inert gas to purge the deposition cavity, and removing residual precursors and byproducts; S6, pulse-feeding a second precursor to enable the second precursor to react with the adsorbed first precursor, and forming a first layer of patterned film in the area of the substrate which is not shielded by the mask plate; s7, repeating the step S5, and purging; S8, increasing the distance between the mask plate and the substrate through the micro-distance adjusting unit, entering a switching mode, switching the driving mechanism to a second mask plate, repeating the step S3 to perform alignment lamination, switching the control system to the second mask plate, and repeating the steps S4 to S7 to form a second layer of patterned film on the first layer of film, wherein the pattern of the second layer of film is the same as or different from that of the first layer of film; and S9, after the deposition of all film layers is completed, carrying out program temperature rise and reduction on the deposition cavity in an inert gas atmosphere, and carrying out in-situ annealing treatment or cooling sampling on the single-layer or multi-layer film.
8. The method of claim 7, wherein in step S4 or S6, the atomic layer deposition cycle is specifically characterized by a precursor pulse time of 0.1-5 seconds, a purge time of 5-60 seconds, and a reactor back pressure of 10-500Pa.
9. The method of claim 7, wherein the heating temperature of the multi-source precursor delivery system is 25-250 ℃, the heating temperature of the deposition chamber is 25-500 ℃, and the primary annealing process temperature of the multi-source, same-chamber deposition chamber is 200-800 ℃.
10. The method of claim 7, wherein the substrate is a silicon wafer, sapphire, glass, flexible polymer or a substrate having a three-dimensional microstructure, and the thin film material includes, but is not limited to, molybdenum disulfide, tungsten disulfide, aluminum oxide, hafnium oxide, silicon nitride, metal, and metal oxide.

Description

Atomic layer deposition equipment and method for integrated in-situ switchable mask plate Technical Field The invention belongs to the technical field of semiconductor manufacturing, relates to atomic layer deposition equipment and method for integrating an in-situ switchable mask plate, and particularly relates to atomic layer deposition (Atomic Layer Deposition, ALD) equipment with in-situ programmable mask plate switching function and a method for preparing a patterned film and a multilayer heterostructure by adopting the equipment. Background The atomic layer deposition technology is a thin film deposition technology based on surface self-limiting reaction, has the characteristics of accurate and controllable atomic-level thickness, good uniformity, excellent step coverage capability and the like, and becomes a key technology in the fields of advanced semiconductor devices, nanotechnology, energy storage and the like. However, conventional ALD apparatus are mainly used for depositing large-area uniform thin films, and it is difficult to directly manufacture devices having complex two-dimensional patterns or precise three-dimensional stacked structures, which is an urgent need for development of modern microelectronic, optoelectronic, and microelectromechanical system (MEMS) devices. Currently, methods for performing ALD patterning are largely divided into post patterning (e.g., photolithography + etching) and pre patterning (e.g., using a mask plate). Post patterning process steps are cumbersome and may damage the deposited film. Although the mask plate method in the pre-patterning is direct, the traditional method needs to open a deposition cavity when the mask plate is replaced every time, destroy the vacuum environment, introduce pollutants (such as water oxygen), seriously affect the interface quality and the device performance, and have low efficiency. In addition, conventional approaches are more difficult to implement for heterostructures requiring multiple materials, multiple patterns stacked sequentially. Chinese patent document CN104213074a discloses an in-situ mask conversion device, but its design is mainly directed to Physical Vapor Deposition (PVD) systems, does not consider the effects of the ALD process specific precursor pulses, purge cycles, and low temperature deposition environment on the mechanism, and is not integrated with multi-source supply and substrate motion control. Chinese patent document CN107338422a discloses a method for preparing molybdenum disulfide thin films by ALD, but does not involve patterned deposition. Chinese patent document CN104805400a relates to a sample transfer and masking device for thin film deposition, which is structurally complex and does not embody the need for precise control in conjunction with ALD self-limiting reaction processes. Therefore, the development of equipment and a method which can switch the mask plate in situ, automatically and accurately under the condition of not breaking vacuum and can be deeply integrated with a multi-source ALD process has great significance for promoting the application of the patterning ALD technology in the micro-nano manufacturing field. Disclosure of Invention In order to solve the problems, the invention discloses atomic layer deposition equipment and an atomic layer deposition method for an integrated in-situ switchable mask plate, which realize automatic replacement of different pattern mask plates in a vacuum environment through a built-in mask plate library and a switching mechanism, and solve the problems of atmosphere pollution and interface oxidation caused by repeated vacuum breaking in the traditional patterning film preparation process. The equipment precisely controls the clearance between the mask plate and the substrate through the micro-distance adjusting unit, and realizes continuous, automatic and high-quality manufacture of the high-resolution patterned film and the complex two-dimensional heterojunction by matching with a multi-source precursor conveying system. In order to achieve the above purpose, the technical scheme of the invention is as follows: An atomic layer deposition apparatus integrating an in-situ switchable mask, comprising: the multi-source precursor conveying system is communicated with the deposition cavity and is used for providing more than two or more precursor sources and purge gas for atomic layer deposition; The deposition chamber is internally provided with a heating sample platform matched with a heater and is used for heating a substrate and providing a vacuum reaction chamber for patterning film manufacture; The built-in mask plate library and the switching mechanism are arranged in the deposition cavity and comprise mask bearing frames used for bearing a plurality of different pattern mask plates and a driving device for driving the mask bearing frames to move so as to select a target mask plate; The micro-distance adjusting unit is arranged on the substrate b