刻蚀装置
By employing the Fizeau interference principle in the etching apparatus and using the observation window as a reference mirror, the problem of interference fringes easily failing in the etching apparatus was solved, achieving high-precision etching depth detection and process control, and improving the quality and efficiency of semiconductor manufacturing.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- 中锃半导体(深圳)有限公司
- Filing Date
- 2025-07-03
- Publication Date
- 2026-07-17
AI Technical Summary
In existing etching devices, the interference fringes of the optical system are prone to failure, resulting in inaccurate etching depth detection, especially in the case of low reflectivity materials or rough surfaces.
Using the Fizeau interference principle, the observation window in the etching chamber is used as a reference mirror to split the detection beam and combine the sampling beam to form an interference image. The interference fringes are captured in real time by a detector, which reduces the dependence of environmental stability on detection and enhances interference contrast.
It achieves high-precision etching depth detection under different materials and working conditions, improves the accuracy and yield of etching processes, and enables real-time etching depth measurement at the sub-nanometer level, overcoming the limitations of traditional methods.
Smart Images
Figure CN224517677U_ABST
Abstract
Claims
1. An etching apparatus, characterized by, include: An etching chamber is provided with a support platform inside the etching chamber. The support platform has a support surface for supporting the object to be etched. The wall of the etching chamber includes an observation window, which is configured to transmit and reflect light incident upon it. The support surface is located within the field of view of the observation window. A detection beam generating unit is configured to generate a detection beam of at least one wavelength and to illuminate the observation window with the detection beam, and to illuminate at least a portion of the support surface after the detection beam is transmitted through the observation window, and to form a sampling beam that is transmitted through the observation window after being reflected by the object to be etched on the support surface, and to form a reference beam with the same propagation path as the sampling beam after the detection beam is reflected by the observation window. And a detector, which is disposed in the coherence region of the sampling beam and the reference beam and forms an interference image.
2. The etching apparatus of claim 1, wherein The detection beam generating unit includes a light source, a beam splitter, and a collimator. The light source is used to emit light of at least one wavelength. The collimator is disposed in the optical path of the light and is used to collimate and converge the light to form a detection beam that illuminates at least a portion of the observation window. The beam splitter is configured to reflect the light to the collimator and to transmit an interference beam formed by the sampling beam and the reference beam to the detector.
3. The etching apparatus of claim 2, wherein The detection beam generating unit further includes a beam expander group, which is disposed in the optical path between the light source and the collimating element.
4. The etching apparatus according to any one of claims 1 to 3, wherein The normal to the reference surface of the observation window is parallel to the light propagation direction of the detection beam, and the reference surface is the surface of the observation window that is away from the etching chamber.
5. The etching apparatus according to any one of claims 1 to 3, wherein The roughness Ra of the reference surface of the observation window is ≤10nm, and the reference surface is the surface of the observation window that is away from the etching chamber.
6. The etching apparatus according to any one of claims 1 to 3, wherein The flatness of the observation window ranges from λ / 5 to λ / 10, where λ is the wavelength of the detection beam.
7. The etching apparatus according to any one of claims 1 to 3, wherein The surface of the observation window facing the etching chamber is matte, and / or the surface of the observation window facing the etching chamber is provided with an anti-reflective coating.
8. The etching apparatus according to any one of claims 1 to 3, wherein The etching apparatus also includes an optical attenuator, which is disposed between the observation window and the support stage.
9. The etching apparatus of claim 2, wherein The light source is a narrow linewidth light source, and the coherence length of the narrow linewidth light source is 100μm-500μm.
10. The etching apparatus according to any one of claims 1 to 3, wherein The etching chamber is also equipped with a purging assembly, and the air outlet of the purging assembly is positioned facing the observation window.