Die including non-rectangular optical material and method of making same

Abstract

To provide a die and / or a wafer which does not exhibit defects and can pass reliability against repetitive thermal cycles and / or thermal shocks.SOLUTION: A die includes a substrate and an optical material, the substrate having a surface defined by a pair of opposing edges, the optical material being non-rectangular in shape and on the surface of the substrate, the optical material not extending the entire length of either edge in the pair of opposing edges. A wafer may include a plurality of dies. Methods of making these wafers and dies are also disclosed.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] FIELD OF THE INVENTION The present invention generally relates to a die that includes a substrate and an optical material, the substrates being opposed to each other. The optical material has a surface defined by opposing edges on both sides, and the optical material has a non-rectangular shape. and on the surface of the substrate, the optical material being at opposing edges of the pair of edges. It does not extend the entire length of either edge. A wafer may contain multiple dies. Methods for making these wafers and dies are also disclosed. [Background technology]

[0002] Background of the Invention Current die-sized light diffusers are mostly circular, rigid The wafer is then fabricated in a single large polymer layer on a solid, optical-quality substrate. Generally, the chip is diced along the dicing line (cutting line for dicing). The dicing lines are parallel to the grid lines. In this way, each die is placed on the glass in a rectangular shape (each side dimension If the are equal, the polymer will have a square shape.

[0003] During dicing of the wafer into dies, the corners and edges of the dies These defects can be caused by the formation of a thin film at the polymer / glass interface. Glass chips may contain voids, and dicing-induced delamination, etc. These defects can lead to die failure during repeated thermal cycling and / or resistance to thermal shock. This can result in failure to meet the reliability specifications.

[0004] In addition, when using a rectangular die, the central area is effectively used. The diffuser is only a small area because most of the incident light beam is circular. Even with the largest beam size passing through the die, most of the corners and edges are , outside the area of ​​active use. Optically redundant and contributing to defect formation are These areas are the corners and most of the edges. Summary of the Invention [Problem to be solved by the invention]

[0005] What is needed is a material that does not exhibit the defects described above and is resistant to repeated thermal cycling and / or thermal shock. Items such as dies and / or wafers that can pass reliability tests. Additionally, the die can be adjusted to accommodate the size of the incident beam from the light source. The material may include non-rectangular shaped materials having dimensions that allow for the material to be molded. [Means for solving the problem]

[0006] In one embodiment, a die is disclosed that includes a substrate and an optical material, the substrates being on opposite sides of each other. and a surface defined by a pair of edges, the optical material being of a non-rectangular shape; The optical material is located on the surface of the substrate at either of the opposing edges of the pair. It does not extend the entire length of the edge.

[0007] In another aspect, a method of making a wafer is disclosed, the method comprising: An optical material is placed on the portion having the relief pattern. forming a non-rectangular shape on each raised relief of the pattern; The substrate is contacted with the optical material to form a film having a thickness ranging from about 20 microns to about 200 microns. imparting a non-rectangular shape to the optical material; and removing the mold. nothing.

[0008] Additional features and advantages of various preferred embodiments are described, in part, in the description that follows and in part. As will be apparent from this description or learned by practicing the various preferred embodiments, Objectives and other advantages of various preferred embodiments may be realized as a result of the elements and methods particularly pointed out in the description herein. This is realized and achieved through the combination of

[0009] Features of the present invention are illustrated by way of non-limiting example in the following figures, in which: Like numbers refer to like elements. [Brief explanation of the drawings]

[0010] [Figure 1] FIG. 1 illustrates a wafer according to one embodiment of the present invention. [Figure 2] Figure 2A is a top view of a die according to one embodiment of the present invention, and Figure 2B is a cross-sectional view of the die. [Figure 3] FIG. 1 illustrates multiple dies with two or more non-rectangular optical materials. [Figure 4] 4A and 4B are diagrams showing a wafer of a comparative example. [Figure 5] 5A and 5B are top and cross-sectional views of a comparative die, respectively; [Figure 6] Figure 6A is a top view of waste after die cutting from the wafer of the comparative example of Figure 4. Figure 6B is a cross-sectional view of waste after die cutting from the comparative example of Figure 6A. [Figure 7] FIG. 1 illustrates a system including a light source and a die, according to one aspect of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0011] Detailed Description of the Invention For simplicity and purposes of explanation, the present invention will be described primarily by reference to examples thereof. In the following description, numerous specific details are set forth in order to provide a thorough understanding of the present invention. However, the present invention may be practiced without limitation to these specific details. In other instances, to avoid unnecessarily obscuring the invention, Some methods and structures are not described in detail.

[0012] In addition, the elements shown in the accompanying drawings may include additional components, Some of the components depicted in the drawings may be removed and / or remodeled without departing from the scope of the present invention. Additionally, elements illustrated in the drawings may not be drawn to scale. and therefore, these elements may be of different sizes and / or dimensions than those shown in the drawings. It may have a shape.

[0013] The foregoing general description and the following detailed description are exemplary and explanatory only and are not intended to limit the invention. It should be understood that the present disclosure is intended to provide a description of various embodiments of the teachings of In a wide variety of embodiments, the die 28, wafer 26, and die The die 28 and the method for fabricating the wafer 26 are disclosed. The die 28 comprises the substrate 10 and the optical material 12. The substrate 10 has a surface defined by opposing pairs of edges. Optical material 12 is non-rectangular in shape and is on the surface of substrate 10. Optical material 12 is It does not extend the entire length of either edge of its opposing pair of edges.

[0014] The wafer 26 is diced to form a plurality of dies 28 having optical material in non-rectangular shapes. By doing so, defects occurring within the die 28 can be minimized. The lower the temperature, the less delamination there will be at the interface 22 between the optical material 12 and the substrate 10. By reducing or eliminating these defects on the die 28, the die 28 can: It can exhibit improved thermal shock reliability and improved performance during thermal cycling. It should be.

[0015] In addition, non-rectangular shapes of the optical material 12 can be accommodated, for example, by the light source 30 and the light shaper. The cross section of the incident beam 32 coming from a shaping (light shaping) optical element (e.g., a diffuser) In this way, the space utilization of the die 28 can be improved. The physical dimensions can be reduced.

[0016] Additionally, the method for fabricating wafers 26 and / or dies 28 may be advantageously implemented with improved efficiency. , because non-rectangular shapes may be present in the optical material 12 during the replication process. In this way, the optical material 12 is provided with an increased thickness. and dimensions can be given to result in a reduction in the cost of the optical material 12.

[0017] FIG. 1 shows a wafer 26 including multiple dies 28. The multiple dies 28 are formed on a common substrate 10. The die 28 is located in an area of ​​the substrate only, e.g., dicing street 14. The dicing street 14 separates two or more dies. 28 and used to dice the wafer 26. The dicing street 14 can be used as a guide (guide line) for The wafer 26 may be a plurality of parallel horizontal and vertical lines forming a pattern. Dice cutting along dicing streets 14 to produce two or more dies 28 and optionally, post-die sawing waste 24 without optical material 12, or substrate 10. For example, in FIG. 1, row 1 and column 1 can be represented as It may be an area outside the optical material 12 (completely free of the optical material 12).

[0018] The substrate 10 can be a circular wafer, or in special cases a square wafer. The substrate 10 can be made of any material suitable for the desired spectral region, such as glass, semiconductor materials, and polymers. In one embodiment, the substrate 10 is glass. , can have a size ranging from about 100 mm to about 300 mm in diameter, or can have a shape If the shape is square, sizes ranging from approximately 50mm x 50mm to approximately 300mm x 300mm are available. In most cases, the thickness of the substrate ranges from about 0.2 mm to about 1.0 mm. At the die level, the substrate 10 may range in size from about 0.5 mm by about 0.5 mm to about 50 mm by about 5 The size of the substrate 10 can range from 0 mm to 100 mm. and can be defined by a first dimension (e.g., length) and a second dimension (e.g., width). At the die level, the substrate 10 may have a surface area ratio of about 1:1 to about 10:1. The substrate 10 may have an aspect ratio (ratio of length to width) of 1000 .mu.m. The surface may have a top surface defined by mating edges 20. In this way, the substrate 10 can be rectangular or square.

[0019] 2A and 2B show the process of dicing the wafer 26 of FIG. 1 along the dicing streets 14. The die 28 includes the substrate 10 and the optical material 12. The substrate 10 is defined by a pair of opposing edges 20. The optical material 12 has a non-rectangular shape and is on the surface of the substrate 10. The material 12 extends along the entire length of either of the opposing edges 20. As shown in FIG. 2A, optical material 12 has a single non-rectangular shape on the surface of substrate 10. As shown in FIG. 2B, the optical material 12 can be formed into a shape such that the optical material 12 is on the opposite side of the optical material 12. In one embodiment, the substrate does not extend the entire length of either edge of the pair of edges. A portion 22 near the edge of the top surface of 10 may be free of optical material 12. In this way, defects may occur at the interface 22 between the optical material 12 and the substrate 10 during dicing. This reduces the likelihood of

[0020] Optical material 12 is a UV (ultraviolet) curable polymer, organic / inorganic host glass The optical quality media may include those selected from inorganic and organic / inorganic hybrid systems. Non-limiting examples of UV curable polymers include free radical curable acrylates, cationic curable Includes cured epoxies, UV-crosslinked polymers, and thermally crosslinked polymers. Organic / inorganic host-guest The system utilizes a dispersion of nanoparticles of different materials to set the refractive index to a desired level. Organic / inorganic hybrid systems include sol-gels, ormosils, and polymers. In one embodiment, the optical material 12 can be a polymer and a sol-gel. You can select from the following:

[0021] The optical material 12 has a non-rectangular shape with a flat bottom surface that interfaces with the top surface of the substrate 10. The optical material 12 can be a single piece that forms a three-dimensional shape with a flat bottom surface. The three-dimensional shape can have more than one surface, such as a pyramid, a pentagonal prism, a hexagonal A group consisting of prismatic, heptagonal, octagonal, hemispherical, cylindrical, and conical shapes. The non-rectangular shape of the optical material 12 is selected from the group consisting of an incident beam 3 from a light source 30. The choice can be made based on the shape of the two.

[0022] As shown in FIGS. 2A and 2B, the flat bottom surface of the optical material 12 overlaps most of the top surface of the substrate 10. As used herein, "substantially" means covering a portion of the surface of the object, but less than the entire surface. It should be understood to mean greater than 50%. The material 12 covers from more than 50% to less than 100% of the surface of the substrate 10; for example, from more than 55% to more than 95%. In another embodiment, the optical material 1 2 does not extend to one or more edges 20 or corners of the substrate 10. The cost of the optical material 12 can be reduced and the possibility of defects being formed due to dicing can be eliminated. This can reduce the risk of

[0023] In one embodiment, the optical material 12 is a non-rectangular shape, such as a cylinder. The diameter is equal to the first dimension of the substrate 10. In other embodiments, the diameter of the cylinder is equal to the first dimension of the substrate 10. The first dimension of the substrate 10 can be the length or width. For example, the optical material 12 may have a thickness ranging from equal to the first dimension of the substrate 10 to 5% of the first dimension of the substrate 10. The non-rectangular shape of the optical material 12 can range in size from It can be sized to match the size of Room32.

[0024] As shown in FIG. 3, the die 28 may be present on the surface of the substrate 10 in two or more non-rectangular shapes. The two or more non-rectangular shapes may include optical material 12. 2. These gaps are formed by the These two or more non-rectangular shapes can be the same shape. or a combination of different shapes. The two or more non-rectangular shapes range from about 2 to about 10 in die 28 .

[0025] In one embodiment, optical material 12 can be present on substrate 10 at a non-uniform thickness. The top surface of the optical material 12 may include a microstructure or a diffraction grating. The thickness of an optical material has two components: the baseline thickness and the nominal thickness. The baseline thickness of the optical material 12 can be from about 0 microns to about 500 microns. For example, from about 0.5 microns to about 480 microns, and as a further example, from about 5 microns The nominal thickness of the optical material can range from 100 microns to about 450 microns. The nominal thickness can include the thickness of the line and the height of the microstructure or grating. 5 microns to about 1000 microns; e.g., about 10 microns to about 900 microns as an additional example, can range from about 20 microns to about 200 microns. do.

[0026] The baseline thickness and nominal thickness values ​​are determined by the refractive index of the substrate 10 at the selected wavelength, Light shaping devices such as light diffusers, gratings, lenses, waveguides, prisms, etc. The refractive index of the optical medium used to fabricate the optical element is determined by a few variables. These values ​​are necessary to control the mechanical stress between the optical material 12 and the substrate 10. It can also be determined based on the requirements and the specific optical functionality of the optical material 12 .

[0027] Also disclosed is a system including a light source 30, as shown in FIG. 7, which emits incident light 32. , incident light 32 can be received by die 28 .

[0028] A method for making wafer 26 is also disclosed, which includes forming a mold with an extruded rib. The optical material 12 is placed on the portion having the roof pattern, and the non-rectangular shape of the optical material 12 is on each raised relief of the pattern; 0, and an optical element having a thickness ranging from about 20 microns to about 1000 microns. The method includes the steps of: imparting a non-rectangular shape to the material 12; and removing the mold. The natural flow dynamics of the liquid allow the circular droplets of optical material 12 to spread out. This allows for control of the diameter and thickness of the optical material 12. In particular, The steps can include controlling the size of the droplets of optical material 12 .

[0029] The method for fabricating the die 28 includes the steps of providing a wafer 26; For example, the optical material 12 may be diced along one or more dicing streets between the separated portions. In one embodiment, the dicing street 14 can be an area of ​​only substrate 10 , ie, without optical material 12 .

[0030] example

[0031] Comparative Example 1 - A conventional wafer 16 is shown in Figures 4A and 4B. The wafer 16 has a circular shape. The substrate 10 is typically glass. An optical material 12, such as a polymer, is placed on the substrate. During the manufacturing process, the wafer 16 is cut along the dicing streets 14. The dicing streets 14 are parallel grid lines. The die 18 is used for the customer's job and produces multiple dies 18 and post-die cutting waste 24. The die cutout waste 24 does not meet customer specifications. As shown in FIG. 5B, the die 18 is a rectangular shaped optical material 12, and is attached to each edge of the substrate 10. 20 (i.e., there are four edges in the rectangle). Glass chips, voids, and dicing-induced delamination during thermal cycling It exhibited defects such as:

[0032] Post-die cut waste 24 may have polymer non-uniformities that do not meet customer specifications. and / or defects formed at the interface between the optical material 12 and the substrate 10, etc. For this reason, those skilled in the art do not consider the dicing streets 14 to be die 18. If used as a standard, the post-die cutting waste 24 includes the entire top row, the entire bottom row, the entire left column, This includes the entire right column, as well as row 2, columns 2 and 7, row 2, columns 1 and 8, etc. Referring to FIG. 4B, There is no waste after die cutting because the dicing lines 14 are This is because the optical material 12 is arranged to optimize its shape. As shown, the post-die cutting waste 24 is held together by opposing mating edges 20. a substrate 10 having a surface defined by a non-rectangular shaped optical material on the surface of the substrate 10; 12, the non-rectangular shaped optical material 12 having opposing paired edges. For ease of understanding, in FIGS. 6A and 6B 1, the non-rectangular shaped optical material 12 extends the entire length of the substrate 10 to the left and below the edge 20. The dicing and thermal cycling also create defects at the interface between the optical material 12 and the substrate 10. is formed.

[0033] Example 1 - Wafer 26 as described herein and shown in Figure 1. Wafer 26 is (preferably) It includes a substrate 10 having a circular (or square) shape, which is generally glass. An optical material 12, such as a silicon dioxide film, was deposited on the substrate 10. During the manufacturing process, the wafer 26 Cut the dice along dicing street 14. Dicing street 14 runs vertically and horizontally. The parallel grid lines are used to form a plurality of dies 28 as disclosed herein. The die 28 is formed according to the customer's specifications. The die 28 has a surface defined by opposing mating edges 20. and a non-rectangular shaped optical material 12 on the surface of the optical substrate 10. The rectangular shaped optical material 12 has edges on either side of the pair of opposite edges. The die 28 does not extend the entire length of the edge, nor does it extend the entire length of the edge as a result of the dicing process itself. Even after repeated thermal cycling, glass chips remain on the glass-optical material interface 22. The chips exhibited no defects such as voids, and dicing-induced delamination.

[0034] From the foregoing description, those skilled in the art will appreciate that the teachings of the present invention can be embodied in a variety of forms. Accordingly, these teachings may be understood in connection with specific embodiments and examples thereof. Although described above, the true scope of the present teachings should not be so limited. Various changes and modifications can be made without departing from the scope of the teachings herein.

[0035] The scope of the disclosure should be broadly construed. The present disclosure encompasses the devices, activities, and methods disclosed herein. Disclose equivalents, means, systems, and methods for achieving the above-mentioned motor and mechanical movements. Each of the disclosed devices, articles, methods, means, mechanical elements or mechanisms With respect to the present disclosure, the present invention provides a method for implementing the numerous aspects, mechanisms, and devices disclosed herein. It is intended that equivalents, means, systems, and methods for performing the method are also encompassed and taught within this disclosure. The claims of this application should be interpreted broadly as well. The description of the invention, in its numerous embodiments, is merely exemplary in nature and therefore should not be construed as limiting the scope of the invention. Modifications that do not depart from the gist of the invention are intended to be within the scope of the invention. The examples should not be construed as a departure from the spirit and scope of the invention.

Claims

1. a substrate having a surface defined by opposing paired edges; an optical material on a surface of the substrate, the optical material being non-rectangular in shape; The optical material is preferably a material having a thickness of at least 100 nm. A die that does not even extend to its full length.

2. The non-rectangular shaped optical material has a flat bottom surface that interfaces with the top surface of the substrate. and one or more surfaces that together with the flat bottom surface form a three-dimensional shape, the three-dimensional shape comprising: Pyramid, pentagonal prism, hexagonal prism, heptagonal prism, octagonal prism, semicircular The die of claim 1 , wherein the die is selected from the group consisting of a sphere, a cylinder, and a cone.

3. The flat bottom surface of the optical material covers most of the top surface of the substrate, but 3. The die of claim 2, wherein the die covers less than the entire area.

4. The die of claim 1 , wherein the non-rectangular shape of the optical material is a cylinder.

5. The die of claim 4 , wherein the diameter of the cylinder is equal to the first dimension of the substrate.

6. The die of claim 4 , wherein the diameter of the cylinder is less than the first dimension of the substrate.

7. 10. The method of claim 1, wherein the optical material is a single non-rectangular shape on the surface of the substrate. Die.

8. the optical material is in two or more non-rectangular shapes on the surface of the substrate, 10. The optical material of claim 1, wherein the non-rectangular shapes are separated one from the other by gaps in the optical material. Die described.

9. 10. The substrate of claim 1, wherein the optical material is absent from a portion of the top surface of the substrate near an edge thereof. stomach.

10. The die of claim 1 , wherein the optical material has a non-uniform thickness.

11. The optical material has a nominal thickness ranging from about 5 microns to about 1000 microns.

10. The die of claim 1.

12. the substrate has a size of about 50 mm x about 50 mm to about 300 mm x about 300 mm; The die of claim 1 .

13. 10. The method of claim 1, wherein the substrate has an aspect ratio of from about 1:1 to about 10:

1. Thailand.

14. The two or more non-rectangular shapes of the optical material range from about 2 to about 10. The die of claim 8 .

15. 10. A wafer comprising a plurality of dies according to claim 1, A wafer in which the plurality of dies share a common contiguous surface of the substrate.

16. The substrate is glass, and the optical material is selected from a polymer or a sol-gel.

16. The wafer of claim 15, which is an optical material.

17. 16. The method of claim 15, wherein the plurality of dies are separated one by one by dicing streets. The wafer described.

18. 1. A method of fabricating a wafer, comprising: placing an optical material on the portion of the mold having the raised relief pattern; forming a non-rectangular shape of the optical material on each of the raised reliefs of the pattern; and A substrate is contacted with the optical material to form a surface having a thickness ranging from about 20 microns to about 200 microns. providing the optical material having a thickness with a non-rectangular shape; removing the mold; A method comprising:

19. The step of disposing the optical material includes controlling the size of the droplets of the optical material.

20. The method of claim 18, comprising:

20. Providing a wafer according to claim 18; dicing the wafer between the separated portions of optical material; A method comprising:

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