CN-121992375-A - Atomic layer deposition equipment and method based on local direct writing technology

CN121992375ACN 121992375 ACN121992375 ACN 121992375ACN-121992375-A

Abstract

The invention discloses atomic layer deposition equipment and a method based on a local direct writing technology, wherein the equipment comprises the following components: the device comprises a deposition cavity defining a vacuum environment, a temperature-controllable precise displacement platform, a movable local reaction unit integrated with a micro reaction head array and a micro-area sealing structure, a three-dimensional micro-motion mechanism for driving the local reaction unit to perform space motion, and a multi-source precursor conveying system. According to the invention, a local closed or semi-closed reaction micro-area is formed on the surface of the substrate through the micro-area sealing structure, and the atomic-level high-quality patterning film is directly drawn according to a preset path under the condition of no need of mask and photoetching by combining the three-dimensional motion control and the alternate pulse time sequence of atomic layer deposition. The invention combines the flexibility of direct-writing printing with the high-quality film growth capability of atomic layer deposition, effectively solves the problem that the traditional ALD technology is difficult to realize high-resolution and complex patterning deposition, and is particularly suitable for flexible manufacture of multilayer heterostructures and complex micro-nano devices.

Inventors

LIU LEI
LU JINGQI
WANG DEYI

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 based on a local write-through technique, comprising: The deposition cavity is internally limited to a vacuum or low-pressure environment, and is internally provided with a temperature-controllable precise displacement platform for bearing and heating a substrate; The integrated precursor supply unit is connected with the injection channel of the micro reaction head array through a heat tracing flexible pipeline and is used for pulse conveying of two or more gaseous precursors and purge gas; The bypass differential exhaust system is respectively connected with the deposition cavity and the tail gas suction channel of the micro reaction head array and is used for establishing cavity background vacuum and directional exhaust of a local reaction zone; The movable local reaction unit is suspended above the temperature-controllable precise displacement platform and comprises a miniature reaction head array and a micro-area sealing structure surrounding the array, wherein the miniature reaction head array comprises at least one group of independent coaxial precursor injection channels and tail gas suction channels; The three-dimensional micro-motion mechanism is connected with the movable local reaction unit and used for driving the movable local reaction unit to move in the X, Y, Z-axis direction and adjusting the relative position between the micro-reaction head array and the substrate; and the control system is used for cooperatively controlling the path planning of the three-dimensional micro-motion mechanism, the pulse time sequence of the integrated precursor supply unit and the temperature and the position of the precise displacement platform.
2. The apparatus of claim 1, wherein the micro-scale seal structure is a contact seal or a pneumatic non-contact seal, wherein when the contact seal is adopted, a high-temperature resistant elastic sealing ring is arranged at the lower end of the structure, the surface of the substrate is pressed by a Z-axis drive under a deposition state to form physical isolation, and when the pneumatic non-contact seal is adopted, an annular inert gas curtain channel is arranged at the periphery of the structure, and precursor diffusion is limited by using a gas flow barrier.
3. The apparatus of claim 1, wherein the integrated precursor supply unit comprises a plurality of independent precursor source bottles, a constant temperature heating jacket, a rapid atomic layer deposition valve, and a mass flow controller.
4. The apparatus of claim 1, wherein the array of micro-reactor heads is of modular design with a nozzle aperture of 50-500 μm and a microchannel heater integrated therein for preventing precursor condensation prior to ejection.
5. The atomic layer deposition device based on the local direct writing technology according to claim 1, further comprising an in-situ vision alignment system, wherein the system comprises a high-resolution camera and a coaxial light source which are arranged outside the deposition cavity, and the alignment mark on the surface of the substrate is observed through a cavity window, and the three-dimensional micro-motion mechanism is controlled in a feedback manner to perform error compensation.
6. A method of preparing a patterned thin film based on the atomic layer deposition apparatus according to any one of claims 1 to 5, comprising the steps of: S1, mounting a substrate on a precise displacement platform in a deposition cavity, vacuumizing and heating the substrate to a preset reaction temperature; S2, driving the movable local reaction unit to move to a first deposition coordinate point by the control system according to preset patterning path data; s3, driving the movable local reaction unit to descend along the Z axis, so that a micro-area sealing structure and the surface of the substrate form a local closed or semi-closed reaction micro-area; s4, alternately introducing a first precursor, purge gas, a second precursor and purge gas into the reaction micro-region according to an atomic layer deposition process sequence to finish N deposition cycles, wherein N is more than or equal to 1; s5, driving the movable local reaction unit to lift or maintain a micro-suspension state along a Z axis, and moving to a next deposition coordinate point along a preset path; s6, repeating the steps S3 to S5 until the deposition of all path points is completed, and forming a patterned film on the substrate; and S7, after the deposition of all the patterned film layers is completed, purging the deposition cavity and cooling and sampling.
7. The method of claim 6, wherein the single pulse time of the atomic layer deposition process sequence in step S4 is 10ms-2S, the pressure in the local reaction micro-area is maintained at 10-1000Pa, the background pressure of the deposition chamber is maintained at 1-50 Pa, a pressure gradient is formed to assist exhaust gas discharge, and the heating temperature of the deposition chamber is 25-800 ℃.
8. The method of preparing a patterned thin film according to claim 6, wherein the three-dimensional relief structure thin film having a thickness gradient is prepared at different regions of the substrate by varying the number of deposition cycles N at different coordinate points in step S4.
9. The method according to claim 6, wherein in the step S6, the control system is used to switch the types of the precursors in the integrated precursor supply unit on line, so as to directly "draw" heterogeneous thin film structures of different materials in different regions of the same substrate.
10. The method of claim 6, wherein the substrate comprises, but is not limited to, a monocrystalline silicon wafer, sapphire, flexible polyimide, glass, or a surface of a mems device having a three-dimensional microstructure.

Description

Atomic layer deposition equipment and method based on local direct writing technology Technical Field The invention belongs to the technical field of semiconductor manufacturing, relates to atomic layer deposition equipment and method based on a local direct writing technology, and particularly relates to equipment and method for maskless preparation of a high-resolution patterned film by combining direct writing path control and atomic layer deposition (Atomic Layer Deposition, ALD) self-limiting reaction characteristics. Background Atomic Layer Deposition (ALD) technology has become a core process in the semiconductor, photovoltaic and nanotechnology fields due to its excellent thickness control capability (atomic scale), excellent uniformity and conformality of high aspect ratio structures. However, conventional ALD processes typically deposit a full coverage of the entire substrate surface. In order to obtain a specific film pattern, two paths are mainly relied on at present, namely 'post-treatment', namely full film deposition is firstly carried out, then redundant parts are removed through photoetching and etching, the process flow is long, the cost is high, and etching liquid can damage sensitive materials, and a 'physical mask', namely a shielding plate is used, wherein the mask is expensive to prepare and difficult to align, and the mask is required to be frequently replaced and repeatedly damaged in a vacuum environment, so that water-oxygen pollution is extremely easy to be introduced, and the interface quality of a film, especially a two-dimensional material heterojunction is seriously influenced. The three-dimensional printing technology, in particular direct-writing (DIW) printing, can realize the local accurate deposition of materials by controlling the motion path of a spray head in a three-dimensional space through a program, and has good pattern design flexibility. However, conventional solution or slurry-based DIW techniques typically deposit films in amorphous or polycrystalline states, and it is difficult to achieve ALD levels of crystalline quality, compactness and thickness uniformity. Therefore, a novel device and a method capable of integrating the high-quality growth characteristic of the ALD thin film and the high-flexibility patterning capability of the DIW technology are developed, and the direct deposition of the high-quality patterning thin film is realized under the condition of no need of mask and photoetching, so that the device and the method have important significance for promoting innovation and development in the fields of flexible electronics, micro sensors, integrated photoelectric devices and the like. Disclosure of Invention In order to solve the problems, the invention discloses atomic layer deposition equipment and method based on a local direct writing technology, which integrate ALD high-quality film forming characteristics with flexible patterning capability of the direct writing technology, have high feasibility, realize maskless patterning, effectively prevent the lateral diffusion of a precursor through a pressure gradient and remarkably improve the definition of the edges of the pattern. In order to achieve the above purpose, the technical scheme of the invention is as follows: An atomic layer deposition apparatus based on a localized direct write technique, comprising: the deposition chamber is internally limited to a vacuum or low-pressure environment, and is internally provided with a temperature-controllable precise displacement platform for bearing and heating a substrate; The integrated precursor supply unit is connected with the injection channel of the micro reaction head array through a heat tracing flexible pipeline and is used for pulse conveying of two or more gaseous precursors and purge gas; The bypass differential exhaust system is respectively connected with the deposition cavity and the tail gas suction channel of the micro reaction head array and is used for establishing cavity background vacuum and directional exhaust of a local reaction zone; The movable local reaction unit is suspended above the temperature-controllable precise displacement platform and comprises a miniature reaction head array and a micro-area sealing structure surrounding the array, wherein the miniature reaction head array comprises at least one group of independent coaxial precursor injection channels and tail gas suction channels; The three-dimensional micro-motion mechanism is connected with the movable local reaction unit and used for driving the movable local reaction unit to move in the X, Y, Z-axis direction and adjusting the relative position between the micro-reaction head array and the substrate; and the control system is used for cooperatively controlling the path planning of the three-dimensional micro-motion mechanism, the pulse time sequence of the integrated precursor supply unit and the temperature and the position of the precise displacement platfor