Electron beam direct writing method and system based on programmable integrated circuit pattern source

Abstract

The application discloses an electron beam direct writing method and system based on a programmable integrated circuit pattern source, and relates to the technical fields of micro-nano processing and electron beam direct writing. The system comprises a programmable integrated circuit chip as a pattern emission source, an electron-optical control module, and a vacuum and workpiece table module. The integrated circuit chip is single-chip integrated with a pixel driving array and an electron emission unit, and can programmably output corresponding spatial distribution electron beam patterns according to a target layout; the electron beam patterns are micro-projected to a wafer surface through an electron-optical system, and patterns corresponding to the target layout are formed on the wafer. The application can inhibit the space charge effect by controlling the electron emission current, emission density or pulse emission mode, does not need a physical mask, can realize parallel and programmable electron beam direct writing, is compatible with the glue exposure and glue-free direct writing processes, has a simple system structure and strong universality, and can be used for micro-nano pattern processing of integrated circuits.

Description

Technical Field

[0001] This invention relates to the field of micro-nano fabrication and electron beam direct writing technology, specifically to an electron beam direct writing method and system based on a programmable integrated circuit pattern source. Background Technology

[0002] Traditional integrated circuit patterning requires physical masks, resulting in high costs and long cycles for pattern replacement. Conventional electron beam direct writing often employs scanning methods, which are inefficient, and the pattern driving and electron emission structures are usually discrete, leading to system complexity, limited array density, and difficulty in achieving high-precision parallel exposure. Parallel electron beam emission is prone to space charge effects, causing electron beam divergence and pattern distortion. Summary of the Invention

[0003] This invention uses a monolithically integrated programmable integrated circuit chip as the electron beam patterning source to achieve maskless, parallel electron beam direct writing. The space charge effect can be suppressed by adjusting the electron emission density, emission current, or by using pulse time-division emission. The system has a simple structure, strong versatility, and is compatible with both adhesive-coated exposure and adhesive-free direct writing.

[0004] Technical solution.

[0005] An electron beam direct writing method is characterized by comprising: using a programmable integrated circuit chip as a pattern emission source, wherein the chip monolithically integrates a pixel driving array and an electron emission unit, and is capable of programmably outputting a spatially distributed electron beam pattern according to a target layout; and projecting the electron beam pattern onto the wafer surface in miniaturized form through an electron optical system to form a corresponding pattern on the wafer.

[0006] Accordingly, the present invention also provides an electron beam direct writing system, characterized in that it includes: a pattern emission source module, which is a programmable integrated circuit chip, with a monolithically integrated pixel driving array and electron emission unit, for outputting an electron beam pattern corresponding to the target layout; an electron optics control module, for focusing and miniaturizing the electron beam pattern; and a vacuum and workpiece stage module, for providing a vacuum environment and aligning the wafer and the pattern.

[0007] This invention requires no physical mask, the pattern is programmable and adjustable, the parallel direct writing efficiency is high, and the space charge effect of the parallel electron beam can be suppressed to ensure pattern accuracy.

[0008] Example 1 (Resin Process): A CMOS integrated circuit chip is used as the pattern emission source. The pixel array is programmed according to the target layout to output a full-width parallel electron beam pattern. By controlling the electron emission density or using pulse emission to suppress the space charge effect, the electron beam pattern is miniaturized and projected onto the resist-coated wafer through an electrostatic lens to form a latent image pattern corresponding to the target layout in the photoresist. After development, the target pattern is obtained.

[0009] Example 2 (Photoresist-free process): Using the same pattern emission source and electron optical system, the wafer is directly written with electron beam, and patterning is achieved through electron beam modification, without the need for photoresist.

[0010] This technology can form a bootstrap chip manufacturing closed loop. After using this system to fabricate higher precision integrated circuit chips, the chips can be directly used as a new generation of pattern emission sources and applied again to this electron beam direct writing system. Through the iterative approach of "fabricating more precise chips with chips", the processing accuracy can be continuously improved, breaking through the inherent bottlenecks of traditional photolithography equipment that are limited by light source wavelength, optical system and processing technology, and realizing the independent iterative upgrade of integrated circuit manufacturing accuracy.

Claims

1. An electron beam direct writing method, characterized in that, include: A programmable integrated circuit chip is provided as a pattern emission source. The chip monolithically integrates a pixel driving array and an electron emission unit, and can programmatically output a spatially distributed electron beam pattern according to the target integrated circuit layout. The electron beam pattern is then miniaturized and projected onto the wafer surface through an electron optical system, forming a pattern corresponding to the target layout on the wafer surface.

2. The method according to claim 1, characterized in that, The electron emission unit is a silicon-based field emission micro-tip structure, and each electron emission unit corresponds to an independent controllable pixel node.

3. The method according to claim 1, characterized in that, The pixel driving array is an addressable array.

4. The method according to claim 1, characterized in that, The scale of the micro-projection is from 10 to 1000 times.

5. The method according to claim 1, characterized in that, The electron beam pattern is formed in parallel as a whole, without the need for scanning and stitching.

6. The method according to claim 1, characterized in that, The direct writing refers to either adhesive-coated exposure or adhesive-free direct writing.

7. The method according to claim 1, characterized in that, Real-time alignment of the wafer and electron beam pattern is achieved through alignment marks on the patterned emission source chip and secondary electron detection.

8. The method according to claim 1, characterized in that, The space charge effect of the electron beam can be suppressed by adjusting the electron emission current, controlling the electron emission density, or using pulse time-division emission.

9. An electron beam direct writing system, characterized in that, include: The pattern emission source module is a programmable integrated circuit chip that monolithically integrates a pixel driving array and an electron emission unit, and is configured to output a spatially distributed electron beam pattern according to the target layout. An electron optics control module, including an electrostatic lens or a magnetic lens, is used to miniaturize and project the electron beam pattern. The vacuum and stage module is used to provide a vacuum environment, support the wafer, and align the wafer with the pattern emitter.

10. The system according to claim 9, characterized in that, The electro-optical control module can switch the scaling ratio by adjusting the working distance.