阅读说明：本技术 一种基于纳米电子源的并行式电子束检测系统 (Parallel electron beam detection system based on nano electron source ) 是由 强鹏飞 盛立志 张雪晗 杨向辉 闫永清 刘哲 李林森 周晓红 赵宝升 于 2021-08-31 设计创作，主要内容包括：本发明提供一种基于纳米电子源的并行式电子束检测系统,该系统是一种高效、高精度并行式电子束检测系统,能够提升电子束检测效率,改善电子束检测像差。该基于纳米电子源的并行式电子束检测系统包括依次设置的纳米阵列电子源、加速电极阵列、样品台、物镜、矫正镜及探测器；纳米阵列电子源基于场发射效应发射多束电子,加速电极阵列对纳米阵列电子源出射的多束电子分别进行加速,样品台接收多束电子并使多束电子穿透样品从而获得样品内部结构信息；多束透射电子束经物镜、矫正镜聚焦并矫正像差后在探测器呈现样品信息图像。(The invention provides a parallel electron beam detection system based on a nano electron source, which is an efficient and high-precision parallel electron beam detection system and can improve the electron beam detection efficiency and the electron beam detection aberration. The parallel electron beam detection system based on the nano electron source comprises a nano array electron source, an accelerating electrode array, a sample stage, an objective lens, a correcting lens and a detector which are arranged in sequence; the nano array electron source emits a plurality of beams of electrons based on a field emission effect, the accelerating electrode array respectively accelerates the plurality of beams of electrons emitted by the nano array electron source, and the sample stage receives the plurality of beams of electrons and enables the plurality of beams of electrons to penetrate through a sample so as to obtain the internal structure information of the sample; and the multi-beam transmission electron beam is focused by the objective lens and the correcting lens, and the image difference is corrected, so that a sample information image is presented on the detector.)

1. A parallel electron beam detection system based on a nanometer electron source is characterized in that: comprises a nano array electron source (11), an accelerating electrode array (12), a sample stage (13), an objective lens (14), a correcting lens (15) and a detector (16) which are arranged in sequence;

the nano-array electron source (11) emits multiple beams of electrons based on a field emission effect, the accelerating electrode array (12) accelerates the multiple beams of electrons emitted by the nano-array electron source (11) respectively, and the sample stage (13) receives the multiple beams of electrons and enables the multiple beams of electrons to penetrate through a sample so as to obtain internal structure information of the sample; the multiple transmitted electron beams are focused by an objective lens (14) and a correcting lens (15) and the image difference is corrected, and then a sample information image is presented on a detector (16).

2. The parallel electron beam inspection system based on nanoelectron sources of claim 1, wherein: each beam of emergent electrons of the accelerating electrode array (12) corresponds to an independent accelerating electrode of the nano-array electron source (11), so that the flight direction of the electron beam is parallel to the optical axis direction of the nano-array electron source (11).

3. The parallel electron beam inspection system based on nanoelectron sources of claim 1 or 2, wherein: the nano array electron source (11) is made of carbon, tungsten oxide, zinc oxide or titanium oxide.

4. A parallel electron beam detection system based on a nanometer electron source is characterized in that: comprises a nano-array electron source (21), an accelerating electrode array (22), a first electron-optical unit, a second electron-optical unit and a detector (28);

the first electron optical unit comprises a first objective lens (23) and a first correcting lens (24); the second electron optical unit comprises a second objective lens (26) and a second correcting lens (27);

the nano-array electron source (21) emits a plurality of beams of electrons based on a field emission effect, the accelerating electrode array (22) accelerates the plurality of beams of electrons emitted by the nano-array electron source (21) respectively, the accelerated plurality of beams of electrons are focused by the first objective lens (23) and the first correcting lens (24) and correct aberrations and then bombard the surface (25) of the device to be detected, and secondary electrons emitted by the surface (25) of the device to be detected are focused by the second objective lens (26) and the second correcting lens (27) and correct aberrations, and then a sample information image is presented on the detector (28).

5. The parallel electron beam inspection system based on nanoelectron source of claim 4, wherein: each beam of emergent electrons of the accelerating electrode array (22) corresponds to an independent accelerating electrode of the nano-array electron source (21), so that the flight direction of the electron beam is parallel to the optical axis direction of the nano-array electron source (21).

6. The parallel electron beam inspection system based on nanoelectron sources of claim 4 or 5, wherein: the nano array electron source (21) is made of carbon, tungsten oxide, zinc oxide or titanium oxide.

Technical Field

The invention relates to the field of electron beam imaging detection, in particular to a parallel electron beam detection system based on a nano electron source.

Background

The electron beam detection has very wide application prospect in the field of material device characterization. Conventionally, the electron beam detection has technical bottlenecks of small number of electron beams, low detection efficiency and the like, so that the detection speed of a detected material and a detected device is greatly reduced. For many years, scientific researchers have been dedicated to research high-efficiency electron beam detection systems, and the electron beam detection efficiency can be improved to a certain extent by increasing the electron beam energy and the beam current, but the electron energy is large, the beam current is too strong, so that the detected material and the detected device are damaged, or the detection resolution is reduced due to the increase of the electron coulomb force.

Disclosure of Invention

In order to improve the electron beam detection efficiency and improve the electron beam detection aberration, the invention provides a parallel electron beam detection system based on a nano electron source, which is an efficient and high-precision parallel electron beam detection system.

In order to achieve the purpose, the invention adopts the following technical scheme:

a parallel electron beam detection system based on a nano electron source comprises a nano array electron source, an accelerating electrode array, a sample stage, an objective lens, a correcting mirror and a detector which are arranged in sequence; the nano array electron source emits a plurality of beams of electrons based on a field emission effect, the accelerating electrode array respectively accelerates the plurality of beams of electrons emitted by the nano array electron source, and the sample stage receives the plurality of beams of electrons and enables the plurality of beams of electrons to penetrate through a sample so as to obtain the internal structure information of the sample; and the multi-beam transmission electron beam is focused by the objective lens and the correcting lens, and the image difference is corrected, so that a sample information image is presented on the detector.

Meanwhile, the invention also provides another parallel electron beam detection system based on the nano electron source, which comprises a nano array electron source, an accelerating electrode array, a first electron optical unit, a second electron optical unit and a detector; the first electron optical unit comprises a first objective lens and a first correcting lens; the second electron optical unit comprises a second objective lens and a second correcting lens; the nano array electron source emits a plurality of beams of electrons based on a field emission effect, the accelerating electrode array respectively accelerates the plurality of beams of electrons emitted by the nano array electron source, the accelerated plurality of beams of electrons are focused by the first objective lens and the first correcting lens and correct aberration and then bombard the surface of the device to be detected, and secondary electrons emitted by the surface of the device to be detected are focused by the second objective lens and the second correcting lens and correct aberration and then present a sample information image on the detector.

Furthermore, the accelerating electrode array corresponds to the nano-array electron source structure, and each beam of emergent electrons corresponds to an independent accelerating electrode, so that the flight direction of the electron beam is parallel to the optical axis direction of the nano-array electron source.

Further, the material of the nano-array electron source is carbon, tungsten oxide, zinc oxide or titanium oxide.

Compared with the prior art, the invention has the following beneficial effects:

the system is an efficient and high-precision parallel electron beam detection system, a nano array electron source has the characteristics of small curvature radius, high electron emissivity and the like, the accelerating electrode array can realize independent control of the emission characteristics of the electron source at different positions, and the objective lens and the correcting lens realize electron focusing and correct electron optical aberration.

Drawings

FIG. 1 is a schematic diagram of a parallel electron beam inspection system according to a first embodiment of the present invention;

FIG. 2 is a schematic diagram of a parallel electron beam inspection system according to a second embodiment of the present invention.

Reference numerals: 11-a nano array electron source, 12-an accelerating electrode array, 13-a sample stage, 14-an objective lens, 15-a correcting lens, 16-a detector, 21-a nano array electron source, 22-an accelerating electrode array, 23-a first objective lens, 24-a first correcting lens, 25-the surface of a device to be detected, 26-a second objective lens, 27-a second correcting lens and 28-a detector.

Detailed Description

The present invention will be described in detail below with reference to the accompanying drawings and specific embodiments. It should be understood by those skilled in the art that these embodiments are only for explaining the technical principle of the present invention and are not intended to limit the scope of the present invention.

In order to improve the electron beam detection efficiency and improve the electron beam detection aberration, the invention provides a parallel electron beam detection system based on a nano electron source. The parallel electron beam system increases the whole beam current, improves the detection efficiency, reduces the beam current density of each single beam, further reduces the influence of the repulsive force between electrons and electrons in the beam current on the imaging resolution, and further improves the resolution reduction problem.

Example one

As shown in fig. 1, the parallel electron beam inspection system based on nano electron source of the present invention includes a nano array electron source 11, an accelerating electrode array 12, a sample stage 13, an objective lens 14, a correcting mirror 15, a detector 16, etc. which are sequentially arranged. The nano-array electron source 11 emits a plurality of beams of electrons under the traction of an accelerating electrode based on a field emission effect, the accelerating electrode array 12 accelerates the plurality of beams of electrons emitted by the nano-array electron source 11 to a certain energy, the sample stage 13 receives the plurality of beams of electrons and enables the electrons to penetrate through a sample so as to obtain the internal structure information of the sample, the objective lens 14 and the correcting lens 15 form an electron optical system, and the electrons penetrating through the sample are focused and imaged to the detector 16 at a fixed zoom ratio.

The accelerating electrode array 12 is arranged below the nano-array electron source 11, the accelerating electrode array 12 corresponds to the nano-array electron source 11 in structure, each beam of emergent electrons corresponds to an independent accelerating electrode, and the arrangement has the advantage that the flight direction of the electron beams is parallel to the direction of an optical axis under the structure. The sample stage 13 is located below the accelerating electrode array 12, and after a plurality of beams of electrons penetrate through the sample, the emergent electrons carry internal structure information of the sample. The objective lens 14 and the correcting lens 15 are arranged below the sample stage 13 and form a set of electron optical unit, and the electron optical unit is used for providing a certain zoom ratio for the transmitted electron beam and reducing imaging aberration.

The nano-array electron source 11 is an array type nano-electron source, materials are not limited to carbon, tungsten oxide, zinc oxide, titanium oxide and the like, electrons obtain initial kinetic energy to accelerate and fly to the sample stage 13 under the action of a certain potential of the accelerating electrode array 12, and the initial potentials of the nano-electron sources at different positions may have differences based on the aberration correction theory. Multiple beams of electrons emitted by the nano array electron source 11 pass through the accelerating electrode array 12 to obtain initial energy, the electrons are transmitted by a sample on the sample stage 13 to obtain electron beams carrying internal information of the sample, and the transmitted electron beams are focused by the objective lens 14 and the correcting lens 15 and correct aberration to present a sample information image on the detector 16.

Example two

The electron beam detection system is not limited to a transmission type imaging system, but also can be applied to an electron beam detection system based on a secondary electron emission system, electrons emitted from the nano-array electron source 21 bombard the surface 25 of the device to be detected after being focused by an accelerating electrode and an electron optical system, and secondary electrons emitted from the surface 25 of the device to be detected are collected by the electron optical system and then imaged at a detector 28.

As shown in fig. 2, the parallel electron beam inspection system based on nano electron source of the present invention comprises a nano array electron source 21, an accelerating electrode array 22, a first electron optical unit, a second electron optical unit and a detector 28; the first electron optical unit comprises a first objective lens 23 and a first correcting lens 24; the second electron optical unit comprises a second objective lens 26 and a second correcting lens 27; the nano-array electron source 21 emits a plurality of electrons based on a field emission effect, the accelerating electrode array 22 accelerates the plurality of electrons emitted by the nano-array electron source 21 respectively, the accelerated plurality of electrons bombard the surface 25 of the device to be measured after being focused and corrected for aberration by the first objective lens 23 and the first correcting lens 24, and the secondary electrons emitted by the surface 25 of the device to be measured are focused and corrected for aberration by the second objective lens 26 and the second correcting lens 27, and then a sample information image is presented on the detector 28.

In this embodiment, the accelerating electrode array 22 corresponds to the nano-array electron source 21, and each emitted electron corresponds to an independent accelerating electrode, so that the flight direction of the electron beam is parallel to the optical axis direction of the nano-array electron source 21. The material of the nano-array electron source 21 is carbon, tungsten oxide, zinc oxide or titanium oxide.