CN-122018249-A - Parallel electron beam imaging lithography system based on micro-electrostatic lens array and control method

CN122018249ACN 122018249 ACN122018249 ACN 122018249ACN-122018249-A

Abstract

The invention discloses a parallel electron beam imaging lithography system based on a micro-electrostatic lens array and a control method, and aims to solve the technical problems that the existing electron beam lithography is low in efficiency, complex in system and incapable of flexible scaling. The system sequentially comprises a unified electron source, a micro-electrostatic lens array, an electron zoom focusing unit, a diaphragm plate and a vacuum sample stage along the moving direction of the electron beam, and further comprises a driving circuit, wherein the unified electron source provides large-area uniform electron beams, the micro-electrostatic lens array realizes the on-off control of the electron beams through focusing/deflection electrodes of each unit, the electron zoom focusing unit adjusts the imaging multiplying power through the voltage proportion of the multi-stage electrostatic electrodes, the diaphragm plate blocks the electron beams in the off state, and the driving circuit synchronously controls the on-off and the zooming multiplying power of the array. The invention realizes scanning-free and one-frame parallel exposure, can flexibly adjust imaging scaling, has the advantages of high integration level, good stability, high exposure efficiency and strong adaptability, and can be used for high-end nano manufacturing scenes such as mask preparation, quantum devices, advanced packaging and the like.

Inventors

CHEN LEI
XU YANG
CHEN RUIBIN

Assignees

陈磊

Dates

Publication Date: 20260512
Application Date: 20260329

Claims (4)

1. A parallel electron beam imaging lithography system based on a micro-electrostatic lens array is characterized by sequentially comprising a unified electron source, a micro-electrostatic lens array, an electron zoom focusing unit, a diaphragm plate and a vacuum sample stage along the movement direction of an electron beam, and further comprising a driving circuit electrically connected with the micro-electrostatic lens array and the electron zoom focusing unit, wherein the unified electron source is used for providing continuous and large-area uniform electron beam current, the micro-electrostatic lens array is composed of a plurality of micro-electrostatic lens units capable of being controlled independently, each unit comprises a focusing electrode and a deflection electrode and is used for realizing the on or off of the electron beam through voltage control, the electron zoom focusing unit is composed of a plurality of stages of coaxial electrostatic electrodes and is used for changing the imaging zoom magnification of the electron beam through adjusting the voltage proportion of each stage of electrodes, the diaphragm plate is used for allowing the electron beam in an on state to pass through and absorbing the deflected electron beam in an off state, the driving circuit is used for controlling the on-off state of each micro-electrostatic lens unit according to an exposure pattern and configuring the magnification of the electron focus unit, when the system works, the electron beam of the on-on unit is focused through the electron focusing unit and projects the electron focusing unit to the wafer, and the electron beam of the electron zoom unit is turned-on or off, and the electron zoom plate is enabled to form the zoom image pattern corresponding to the zoom pattern on the surface of the image zoom pattern.
2. A parallel electron beam imaging photoetching control method based on a micro-electrostatic lens array is characterized by comprising the steps of generating continuous and uniform electron beams by a unified electron source, comprehensively irradiating the micro-electrostatic lens array, configuring electrode voltage of an electronic zoom focusing unit according to target exposure resolution, setting imaging zoom magnification, converting a pattern to be exposed into matrix switch signals of the micro-electrostatic lens array, independently applying focusing voltage or deflection voltage to each micro-electrostatic lens unit to enable the corresponding electron beams to be conducted and transmitted or deflected and blocked, enabling the conducted electron beams to zoom and focus through the electronic zoom focusing unit, forming parallel nano exposure patterns on the surface of a wafer through a diaphragm plate, and realizing multi-frame splicing through stepping movement of a vacuum sample stage to complete large-area exposure.
3. The system of claim 1, wherein the array of micro-electrostatic lenses is monolithically integrated using MEMS technology, the cells being isolated from each other and individually addressable.
4. The system of claim 1, wherein the electronic zoom focusing unit achieves continuously variable magnification or reduction imaging by voltage proportioning of multi-stage electrostatic electrodes.

Description

Parallel electron beam imaging lithography system based on micro-electrostatic lens array and control method Technical Field The invention belongs to the technical field of electron beam lithography and micro-nano processing, and particularly relates to a system and a control method for realizing scanning-free, variable-magnification and parallel imaging type electron beam exposure by adopting a unified electron source and combining an addressable micro-electrostatic lens array and an electron zoom focusing unit. Background The traditional single-beam electron beam lithography adopts a point-by-point scanning mode, has low writing efficiency, and is difficult to meet the manufacturing requirement of a large-scale nano structure. The existing multi-beam electron beam system adopts a multi-electron source array or a beam splitting structure, and has the problems of poor uniformity of electron sources, complex system, high alignment difficulty, low integration level and the like. Meanwhile, most of traditional imaging electron beam optical systems are fixed-magnification imaging, and the image scaling ratio cannot be flexibly adjusted according to different processing scenes, so that the application range is limited. Disclosure of Invention Technical problem The invention solves the following defects in the prior art: The uniformity, stability and service life of the multi-electron source array are difficult to meet the requirements of mass production lithography; The traditional parallel electron beam system has a complex structure and cannot realize monolithic integration and CMOS compatible driving; The existing electron beam imaging scheme is fixed in multiplying power, does not have scaling and adjusting capability, and cannot adapt to the nano processing requirements of multiple scales and multiple resolutions; an imaging exposure scheme which realizes electron beam on-off only through electric field regulation and control, does not need mechanical action and can be integrated in large scale is lacking. Technical proposal 1. System architecture The parallel electron beam imaging lithography system based on the micro-electrostatic lens array sequentially comprises a unified electron source, the micro-electrostatic lens array, an electron zoom focusing unit, a diaphragm plate, a vacuum sample stage and a driving circuit connected with the micro-electrostatic lens array and the electron zoom focusing unit along the movement direction of the electron beam; The uniform electron source is used for generating continuous, large-area, high-brightness and uniformly distributed electron beam, and the whole electron beam irradiates the whole working surface of the rear micro-electrostatic lens array; The micro-electrostatic lens array is composed of a plurality of independent micro-electrostatic lens units arranged in a matrix, each micro-electrostatic lens unit comprises at least one group of focusing electrodes and one group of deflection electrodes, and the electrodes are mutually insulated and can be independently applied with voltage. The micro-electrostatic lens array is only used for carrying out electric control on-off and preliminary focusing control on electron beams from a unified electron source, wherein when a focusing voltage is applied to a certain micro-electrostatic lens unit, the unit is in an on state, and the electron beams are restrained and axially transmitted; The electronic zoom focusing unit consists of a multistage coaxial annular electrostatic electrode, is positioned between the micro electrostatic lens array and the diaphragm plate, can continuously adjust the imaging multiplying power of the electron beam by changing the voltage proportion of each stage of electrode, realizes the amplification, shrinkage or focusing adjustment of the electron beam, and enables the electron beam transmitted by the conducting unit to finally form a nano-scale focusing light spot with a required size on the surface of a wafer; The aperture plate is provided with light holes corresponding to the units of the micro-electrostatic lens array, only the electron beams in the on state and axially transmitted are allowed to pass through, and the deflected electron beams in the off state irradiate the non-aperture area of the aperture plate to be absorbed and blocked, so that the deflected electron beams cannot reach the rear wafer. The vacuum sample stage is used for bearing a wafer to be exposed and can realize high-precision stepping movement so as to finish spliced large-area exposure of multi-frame images; The driving circuit is used for synchronously outputting control signals to the micro-electrostatic lens array and the electronic zoom focusing unit, controlling the on and off of each micro-electrostatic lens unit according to the pattern to be exposed, and adjusting the zoom magnification of the electronic zoom focusing unit according to the target resolution. Control method A parallel electron beam imagin