Dark field rectangular illumination system for semiconductor inspection

Abstract

The utility model provides a kind of dark field rectangular illumination system for semiconductor detection, including LED light source, optical fiber coupling component, light guide stick and lens group, the light emitted by the LED light source becomes rectangular light by the optical fiber coupling component, the light coupling of the optical fiber coupling component into the light guide stick, again, the lens group is shaped as uniform rectangular light spot.The utility model solves the problem of uneven dark field illumination spot and poor size adaptability by compact optical design, suitable for high-precision detection of semiconductor wafer.Lens group adopts full separation design, the curvature radius of each lens is optimized to reduce aberration and improve light energy utilization.

Description

Technical Field

[0001] This utility model relates to the field of semiconductor wafer inspection technology, and in particular to a dark field rectangular illumination system for semiconductor inspection. Background Technology

[0002] In semiconductor wafer inspection, dark-field illumination can identify surface defects by capturing scattered light. Current technologies often employ ring or circular light spots in dark-field illumination, which are difficult to adapt to rectangular inspection areas and suffer from poor spot uniformity. Some solutions adjust the spot shape using complex optical components, but these suffer from large size, high light energy loss, and insufficient multi-band compatibility, affecting inspection efficiency and accuracy.

[0003] Therefore, it is necessary to provide a new approach to solve the aforementioned technical problems. Utility Model Content

[0004] In order to achieve the above-mentioned objectives and other advantages of this utility model, the purpose of this utility model is to provide a dark field rectangular illumination system for semiconductor detection, including an LED light source, an optical fiber coupling component, a light guide rod and a lens group. The light emitted by the LED light source is converted into rectangular light output by the optical fiber coupling component, the light output by the optical fiber coupling component is coupled into the light guide rod, and then shaped into a uniform rectangular light spot by the lens group.

[0005] Furthermore, the optical fiber coupling assembly includes an optical fiber, the light inlet of which uses a circular optical fiber for light reception, and the light outlet of which the optical fibers are rearranged and combined into a rectangle.

[0006] Furthermore, the lens group includes multiple optical lenses with specific radii of curvature to optimize optical path transmission efficiency.

[0007] Furthermore, the lens group comprises three lenses, which are arranged in sequence according to the direction of light transmission: a first lens, a second light-transmitting lens, and a third lens.

[0008] Furthermore, the first surface of the first lens is a plane, and the radius of curvature of the second surface is 41-42 mm;

[0009] The first surface of the second lens is a plane, and the radius of curvature of the second surface is 32-33 mm;

[0010] The first surface of the third lens is a plane, and the radius of curvature of the second surface is 51-52 mm.

[0011] Furthermore, the thickness of the first lens is 4-6 mm, the thickness of the second lens is 3.5-5.5 mm, and the thickness of the third lens is 5-7 mm.

[0012] Furthermore, the first lens, the second lens, and the third lens are all fused silica lenses.

[0013] Furthermore, the spacing between the first lens is 19–21 mm, the spacing between the second lens is 12.2–14.2 mm, and the spacing between the third lens is 51–53 mm.

[0014] Furthermore, the light guide rod has a size of 9×1.7mm.

[0015] Furthermore, the size of the rectangular light spot is 28×5.3mm.

[0016] Compared with the prior art, the beneficial effects of the embodiments of this utility model are:

[0017] This invention provides a dark-field rectangular illumination system for semiconductor inspection. Through a compact optical design, it solves the problems of uneven light spots and poor size adaptability in existing dark-field illumination systems, making it suitable for high-precision inspection of semiconductor wafers. The lens group adopts a fully separable design, and the curvature radius of each lens is optimized to reduce aberrations and improve light energy utilization.

[0018] The above description is merely an overview of the technical solution of this utility model. In order to better understand the technical means of this utility model and to implement it according to the contents of the specification, the preferred embodiments of this utility model are described in detail below with reference to the accompanying drawings. The specific implementation methods of this utility model are given in detail in the following embodiments and their accompanying drawings. Attached Figure Description

[0019] The accompanying drawings, which are included to provide a further understanding of the present invention and form part of this application, illustrate exemplary embodiments of the present invention and, together with the description thereof, serve to explain the present invention and do not constitute an undue limitation thereof. In the drawings:

[0020] Figure 1 A schematic diagram of a dark-field rectangular illumination system used for semiconductor testing;

[0021] Figure 2 Fiber optic diagram Figure 1 ;

[0022] Figure 3 Fiber optic diagram Figure 2 ;

[0023] Figure 4 This is a schematic diagram of the light-inlet and light-outlet surfaces of an optical fiber.

[0024] Figure 5 Schematic diagram of light guide rod and lens assembly Figure 1 ;

[0025] Figure 6 Schematic diagram of light guide rod and lens assembly Figure 2 ;

[0026] Figure 7 Schematic diagram of lens group Figure 1 ;

[0027] Figure 8 Schematic diagram of lens group Figure 2 ;

[0028] Figure 9 This is a schematic diagram of a rectangular light spot.

[0029] In the diagram: 1. Light box; 2. Optical fiber; 21. Light inlet; 211. Light inlet surface; 22. Light outlet; 221. Light outlet surface; 3. Light guide rod; 4. Lens group; 41. First lens; 42. Second lens; 43. Third lens. Detailed Implementation

[0030] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of them. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of the present invention.

[0031] In the accompanying drawings, shapes and dimensions may be enlarged for clarity, and the same reference numerals will be used in all figures to indicate the same or similar parts.

[0032] In the following description, terms such as center, thickness, height, length, front, back, rear, left, right, top, bottom, upper, and lower are defined relative to the structure shown in the accompanying drawings. In particular, "height" corresponds to the dimension from top to bottom, "width" corresponds to the dimension from left to right, and "depth" corresponds to the dimension from front to back. These are relative concepts and may vary depending on their location and usage. Therefore, these or other orientations should not be interpreted as restrictive terms.

[0033] Terms involving attachment, connection, etc. (e.g., “connection” and “attachment”) refer to the relationship in which these structures are directly or indirectly fixed or attached to each other through an intermediate structure, as well as movable or rigid attachments or relationships, unless otherwise explicitly stated.

[0034] Example 1

[0035] A dark-field rectangular illumination system for semiconductor inspection, such as Figures 1-8As shown, the system includes an LED light source, an optical fiber coupling assembly, a light guide rod 3, and a lens group 4. Light emitted from the LED light source is amplified into a rectangular beam by the optical fiber coupling assembly. The light from the optical fiber coupling assembly is coupled into the light guide rod, and then shaped into a uniform rectangular light spot by the lens group. Figure 9 As shown.

[0036] In this embodiment, the LED light source is installed inside the light box 1. The light emitted from the light box is transformed into rectangular light through a specially designed optical fiber. The light from the optical fiber is coupled into a rectangular light guide rod and shaped into a uniform rectangular light spot by the optical system. Finally, it is imaged onto the surface of the object being measured to form a rectangular light spot.

[0037] In some embodiments, such as Figures 1-3 As shown, the fiber optic coupling assembly includes an optical fiber 2. The optical fiber's inlet 21 uses a circular optical fiber for light collection, thus ensuring beam quality. The optical fiber's outlet 22 has its fibers rearranged and combined into a rectangle. Figure 4 As shown in (a), the light-incident surface 211 of the light-incident port 21 of the optical fiber 2 is circular; as Figure 4 As shown in (b), the light-emitting surface 221 of the light-emitting port 22 of the optical fiber 2 is rectangular.

[0038] In this embodiment, the light guide rod (9×1.7mm) receives the optical signal transmitted through the optical fiber at its input end, and the output end is magnified and imaged by a lens group. Furthermore, the lens group includes multiple optical lenses with specific radii of curvature to optimize optical path transmission efficiency and achieve uniform rectangular illumination of the object surface (28×5.3mm).

[0039] In some embodiments, such as Figures 5-8 As shown, the lens group 4 includes three lenses, which are arranged in the order of light transmission direction as first lens 41, second lens 42, and third lens 43.

[0040] Furthermore, the first surface of the first lens (L1) is a plane (R1=∞), and the radius of curvature R2 of the second surface is 41~42mm;

[0041] The first surface of the second lens (L2) is a plane (R3 = ∞), and the radius of curvature of the second surface R4 is 32-33 mm;

[0042] The first surface of the third lens (L3) is a plane (R5=∞), and the radius of curvature R6 of the second surface is 51~52mm.

[0043] Furthermore, the thickness of the first lens is 4-6 mm, the thickness of the second lens is 3.5-5.5 mm, and the thickness of the third lens is 5-7 mm.

[0044] Furthermore, the first lens, the second lens, and the third lens are all fused silica lenses.

[0045] Furthermore, the spacing between the first lens is 19–21 mm, the spacing between the second lens is 12.2–14.2 mm, and the spacing between the third lens is 51–53 mm.

[0046] Preferably, the spacing and material parameters of the first lens, the second lens, and the third lens are as follows:

[0047]

[0048]

[0049] With the above design, the rectangular spot size error is ≤ ±0.2mm and the edge uniformity is >90%, which meets the requirements of semiconductor testing.

[0050] This invention solves the problems of uneven light spots and poor size adaptability in existing dark-field illumination through a compact optical design, making it suitable for high-precision inspection of semiconductor wafers. The lens group adopts a fully separable design, and the radius of curvature of each lens is optimized to reduce aberrations and improve light energy utilization.

[0051] This embodiment can further expand the function of the garment care device, such as agitating the clothes during the washing process to enhance the washing effect, clamping the washed clothes to hang them to dry, or performing cleaning actions on the washing environment inside the drum to optimize the washing environment, thereby optimizing the overall function of the garment care device, meeting different user needs, and improving the user experience.

[0052] Although the embodiments of this utility model have been disclosed above, they are not limited to the applications listed in the specification and embodiments. They can be applied to various fields suitable for this utility model. For those skilled in the art, other modifications can be easily made. Therefore, without departing from the general concept defined by the claims and their equivalents, this utility model is not limited to the specific details and the illustrations shown and described herein.

Claims

1. A dark-field rectangular illumination system for semiconductor detection, characterized in that: It includes an LED light source, an optical fiber coupling component, a light guide rod, and a lens group. The light emitted by the LED light source is converted into a rectangular light output by the optical fiber coupling component. The light output by the optical fiber coupling component is coupled into the light guide rod, and then shaped into a uniform rectangular light spot by the lens group.

2. The dark-field rectangular illumination system for semiconductor detection as described in claim 1, characterized in that: The optical fiber coupling assembly includes an optical fiber, wherein the optical fiber inlet uses a circular optical fiber for light reception, and the optical fiber outlet is rearranged and combined into a rectangle.

3. The dark-field rectangular illumination system for semiconductor detection as described in claim 1, characterized in that: The lens group comprises multiple optical lenses with specific radii of curvature to optimize optical path transmission efficiency.

4. A dark-field rectangular illumination system for semiconductor detection as described in claim 3, characterized in that: The lens group comprises three lenses, which are arranged in the order of light transmission direction as a first lens, a second light-transmitting lens, and a third lens.

5. A dark-field rectangular illumination system for semiconductor detection as described in claim 4, characterized in that: The first surface of the first lens is a plane, and the radius of curvature of the second surface is 41~42mm; The first surface of the second light-transmitting mirror is a plane, and the radius of curvature of the second surface is 32~33mm; The first surface of the third lens is a plane, and the radius of curvature of the second surface is 51~52mm.

6. A dark-field rectangular illumination system for semiconductor detection as described in claim 5, characterized in that: The thickness of the first lens is 4-6 mm, the thickness of the second lens is 3.5-5.5 mm, and the thickness of the third lens is 5-7 mm.

7. A dark-field rectangular illumination system for semiconductor detection as described in claim 5, characterized in that: The first lens, the second lens, and the third lens are all fused silica lenses.

8. A dark-field rectangular illumination system for semiconductor detection as described in claim 5, characterized in that: The spacing between the first lens is 19~21mm, the spacing between the second lens is 12.2~14.2mm, and the spacing between the third lens is 51~53mm.

9. A dark-field rectangular illumination system for semiconductor detection as described in claim 1, characterized in that: The light guide rod measures 9 × 1.7 mm.

10. A dark-field rectangular illumination system for semiconductor detection as described in claim 1, characterized in that: The rectangular light spot has a size of 28×5.3mm.

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