KR20180069693A - Optical chip and manufacturing method thereof - Google Patents

Abstract

The present invention relates to an optical chip which can prevent a lens from being contaminated, and a manufacturing method thereof. The method comprises the steps of: providing a wafer including a plurality of optical chips wherein, each of the optical chips includes a plurality of pixels, and each of the pixels includes a lens; forming a lens protective layer on the lens of the pixel of the optical chip; separating the optical chip by cutting the wafer; arranging the separated optical chip on a substrate; and removing the lens protective layer from the lens of the pixel of the optical chip.

Description

TECHNICAL FIELD The present invention relates to an optical chip and a manufacturing method thereof,

The present invention relates to an optical chip and a manufacturing method thereof. More particularly, the present invention relates to an optical chip for mounting a lens protection layer in a manufacturing process, and a manufacturing method thereof.

In the manufacture of optical chips, such as photosensitive chips, the lenses used to collect light are often contaminated by unavoidable factors. Contaminated lenses can cause defects such as particle defects or damage, which can affect the optical effects of the lens as well as affect yields in severe cases by preventing the optical chip from operating normally.

An object of the present invention is to provide an optical chip and a method of manufacturing the same that can solve the above problems.

In one aspect, an optical chip manufacturing method includes providing a wafer comprising a plurality of optical chips, wherein each optical chip comprises a plurality of pixels, each pixel comprising a lens; Forming a lens protection layer on a lens of a pixel of the optical chip; Separating the optical chip by cutting the wafer; Disposing the separated optical chip on a substrate; And removing the lens protection layer from the lens of the pixel of the optical chip.

In another aspect, the optical chip includes a plurality of pixels and a plurality of lens protective layers. Each of the pixels includes an optical member, and a lens is provided on the optical member. Each of the lens protective layers is provided on a lens.

According to the present invention, there is provided an optical chip and a manufacturing method thereof capable of solving the above problems.

BRIEF DESCRIPTION OF THE DRAWINGS The invention will be better understood from the following detailed description taken in conjunction with the accompanying drawings, in which: FIG. It should be noted that, in accordance with industry standard practice, the various structures are not designed to scale. In practice, the dimensions of various structures can be arbitrarily enlarged or reduced for clarity of description.
1 to 11 are explanatory views showing a method of manufacturing an optical member according to some embodiments of the present invention.
To denote the same or similar elements, common reference numerals have been used throughout the drawings and specific embodiments. The embodiments of the present invention will become more apparent from the following detailed description with reference to the accompanying drawings.

Unless otherwise specified, the terms "top," "bottom," "top," "left," "right," "down," "top," "bottom," " Quot; side, "" higher than "," lower ", " upper ", "upward "," downward " It should be understood that the spatial description used in the text is merely for the purpose of explanation and that, if practiced in the text, the advantages of embodiments of the present invention may be placed in a space in any direction or manner under conditions that do not cause variation due to placement .

As used herein, the terms "first" and "second" are used to describe various members, assemblies, regions, layers and / or sections, but such members, assemblies, regions, layers and / And should not be limited by these terms. These terms may only be used to distinguish one member, assembly, region, layer or section from another member, assembly, region, layer or section. It is not intended to imply that there is an order when the terms "first" and "second" are used in the text unless the context clearly dictates otherwise.

The embodiment of the present invention effectively protects the lens of the optical chip through the method of forming the lens protection layer covering the lens of the optical chip on the wafer in advance so as to prevent the lens from being damaged or contaminated in the subsequent manufacturing process And further increases the yield of the optical chip. In some embodiments, the lens protection layer can be removed from the lens after the fabrication process is complete. In some other embodiments, the lens protection layer may be preserved on the lens after the fabrication process is complete.

1 to 11 are explanatory views showing a method of manufacturing an optical member according to some embodiments of the present invention. Referring to Figure 1, a wafer 10 is provided. The wafer 10 includes a plurality of optical chips 12 wherein each optical chip 12 includes a plurality of pixels 14 and each pixel 14 includes one or more lenses 20 do. In some embodiments, the wafer 10 may include, but is not limited to, semiconductor wafers such as silicon wafers. In some embodiments, each of the pixels 14 includes one or more optical members 16, and the lenses 20 are mounted on the optical member 16. In some embodiments, optical member 16 includes a photosensitive member such as a CMOS image sensor (CIS) chip, a charge coupled (CCD) image sensing member, a photodiode, or other type of photosensitive member . In other embodiments, the optical member 16 may comprise a light emitting member such as a light emitting diode (LED) chip or other type of light emitting member. In some embodiments, the optical chip 12 may further include a color filter 18 disposed between the optical member 16 and the lens 20. For example, the color filter 18 may include a red filter, a green filter, a blue filter, and other color filters.

Then, the lens protection layer 22 is formed on the lens 20 of the pixel 14 of the optical chip 12. [ In some embodiments, the cleaning process may be performed on the lens 20 before forming the lens protection layer 22. For example, deionized water or a chemical solvent may be used to remove particles on the surface of the lens 20 to increase the adhesion between the lens protective layer 22 and the lens 20. In some embodiments, the method of forming the lens protective layer 22 on the lens 20 may be as described below.

Referring to FIG. 2, a hydrophilic liquid protective material is formed on the lens 20 of the pixel 14 of the optical chip 12. In some embodiments, the hydrophilic liquid protective material can be selected as a material that is water-soluble at room temperature and can be changed to hydrophobic after heating, so that the lens 20 is not easily damaged during the process of forming the lens protective layer 22, Moisture is not easily left on the protective layer 22. In some embodiments, the hydrophilic liquid protective material may have the chemical structure as in formula (1) below.

Wherein R1 is a hydrophilic group,

R2 and R3 are a polymerizable group,

C is a cleavage group.

For example, the hydrophilic liquid phase protective material may include, but is not limited to, a mixture of polyurethane and 2-isopropoxyethanol. In some embodiments, the weight percent of polyurethane is from about 60% to about 80%, the weight percent of 2-isopropoxyethanol is from about 10% to about 30%, the weight of polyurethane and 2-isopropoxyethanol % Is less than 100%. In some embodiments, the hydrophilic liquid protective material may comprise suitable additives. In some embodiments, the hydrophilic liquid protective material is formed on the lens 20 of the pixel 14 of the optical chip 12, but not limited thereto, within a temperature range of about 20 캜 to about 30 캜. In some embodiments, the process of forming the hydrophilic liquid phase protective material may include a spin coating process, a spray coating process, a dipping process, or other suitable process. For example, a hydrophilic liquid protective material can be used to form a hydrophilic liquid protective material on the wafer 10 by using a hydrophilic liquid protective material to carry out a spin-coating process for a certain period of time within a certain number of revolutions per minute (RPM).

In some embodiments, the hydrophilic liquid protective material of formula (1) can form a polymer such as formula (2) by heating after heating to form a polymerization reaction with the R2 group and the R3 group, wherein n represents the degree of polymerization.

Referring to FIG. 3, the hydrophilic liquid protective material polymerizes the hydrophilic liquid protective material through the baking step 24 to form the lens protective layer 22. [0034] FIG. In some embodiments, the temperature of the baking process 24 is less than 100 ° C., in one embodiment about 100 ° C. to 150 ° C., the time of the baking process 24 is less than 10 minutes, To about 3 minutes, but is not limited thereto. In some embodiments, the thickness of the lens protective layer 22 is less than 10 microns, and in one embodiment from about 0.5 microns to about 5 microns, but is not limited thereto. In some embodiments, the lens protective layer 22 is a transparent protective layer. In some embodiments, the lens protection layer 22 has a substantially flat surface so that the lens protection layer 22 can be secured on the support plate in a subsequent process. In some embodiments, the lens protective layer 22 is a conformal protective layer formed substantially along the contour of the lens protective layer 22.

Referring to FIG. 4, the surface of the lens protective layer 22 is fixed on the first support plate 26. In some embodiments, the first foot plate 26 includes a tape or other soft / lightweight pedestal. In some embodiments, the thickness of the wafer 10 is reduced from the backside of the wafer 10 when the wafer 10 is thinned, as shown in FIG. In some embodiments, a method of thinning a wafer may include, but is not limited to, a grinding process using a grinder 28.

Referring to Fig. 6, the back surface of the wafer 10 is fixed on the second support plate 30. Fig. In some embodiments, the second footing plate 30 includes a tape or other soft / lightweight pedestal. Referring to Fig. 7, the first support plate 26 is removed from the surface of the lens protection layer 22. Referring to FIG. 8, the wafer 10 is cut to separate a plurality of optical chips 12. In some embodiments, the wafer cutting method may include, but is not limited to, using a cutting tool 32 to advance the cutting process.

Referring to FIG. 9, the optical chip 12 whose inspection result is normal is lifted from the second support plate 30. In some embodiments, the optical chip 12 can be lifted from the second support plate 30 using the clamp 34. [ Referring to FIG. 10, the optical chip 12 is then relocated on the substrate 36.

In some embodiments, the lens protection layer 22 may be preserved on the lens 20 of the pixel 14 of the optical chip 12. In some embodiments, the lens protection layer 22 can be removed from the lens 20 of the pixel 14 of the optical chip 12, as shown in Fig. In some embodiments, removing the lens protection layer 22 from the lens 20 of the pixel 14 of the optical chip 12 includes removing the lens protection layer 22 using a chemical cleaning solution . In some embodiments, the chemical cleaning solution has weak alkalinity. In one embodiment, the principle of removing the lens protection layer 22 using a chemical cleaning solution may be as shown in equation (3) below.

In some embodiments, the chemical cleaning solution comprises an R4 group and a R5 group, and under weakly alkaline conditions the R4 group and the R5 group can be easily charged. Here, the R4 group which is negatively charged attacks the carbonyl group of the pyrolytic group of the lens protective layer 22 and bonds with the carbonyl group, and the oxygen atom of the lens protective layer 22, which has a negative charge, Is bonded to the R5 group. Thus, the lens protective layer 22 can be pyrolyzed into two water-soluble products of the above formula, dissolved in a chemical cleaning solution and removed.

In some embodiments, the chemical cleaning solution comprises a mixed solution of dimethyl sulfoxide, diethylene glycol monobutyl ether, and polyoxyethylene polyoxypropylene polymer. In some embodiments, the weight percent of dimethyl sulfoxide is about 60% to about 80%, the weight percentage of diethylene glycol monobutyl ether is about 10% to about 30%, the weight of the polyoxyethylene polyoxypropylene polymer % Is about 1% to about 5%, and the weight percent of dimethyl sulfoxide, diethylene glycol monobutyl ether, and polyoxyethylene polyoxypropylene polymer is 100% or less. In some embodiments, the chemical cleaning solution may comprise suitable additives. In some embodiments, the temperature of the step of removing the lens protective layer 22 using a chemical cleaning solution is from about 20 캜 to about 30 캜, the removal time is less than 300 seconds, and in one embodiment from about 30 seconds to about 120 seconds However, the present invention is not limited thereto. In some embodiments, the chemical cleaning solution may be sprayed onto the lens protective layer 22 to remove the lens protective layer 22. [ In some embodiments, the lens protection layer 22 can be removed by immersing the lens protection layer 22 in a chemical cleaning solution. In some embodiments, the chemical cleaning solution has good wettability. In some embodiments, after the step of removing the lens protection layer 22 from the lens 20 of the pixel 14 of the optical chip 12, a cleaning process may be performed on the wafer 10.

The embodiment of the present invention effectively protects the lens of the optical chip through the method of forming the lens protection layer covering the lens of the optical chip on the wafer in advance so as to prevent the lens from being damaged or contaminated in the subsequent manufacturing process And further provides an optical chip manufacturing method for increasing the yield of the optical chip. The lens protective layer may be made of a material that is water-soluble at room temperature and hydrophobic after heating. The lens protection layer can be easily removed using a chemical cleaning solution, so that the lens is not damaged.

As used herein, the terms "about", "essentially", "basic" and "about" are used to describe and consider small changes. When used in conjunction with an event or situation, these terms refer to instances where the event or circumstance is clearly evident, and an instance very similar to the occurrence of the event or circumstance. For example, when used in combination with numeric values, these terms refer to a range of variation of less than ± 10% of the value (eg ± 5% or less, ± 4% or less, ± 3% or less, ± 2% or less, ± 1 % Or less, ± 0.5% or less, ± 0.1% or less, or ± 0.05% or less).

While the invention has been described and illustrated with reference to specific embodiments thereof, such description and description are not intended to limit the invention. It should be understood by those skilled in the art that various changes may be made and equivalents may be substituted without departing from the true spirit and scope of the invention as defined in the claims. Explanations do not necessarily have to be made in proportion. Due to the manufacturing process and tolerance limits, there may be differences between the reproduction of the process of the present invention and the actual equipment. There may also be other embodiments of the present invention that are not specifically described. The specification and drawings are to be regarded as illustrative and not restrictive. The specific situation, material, composition of matter, method or process may be modified to suit the purpose, spirit and scope of the present invention. All such calibrations are deemed to be within the scope of the claims appended hereto. It should be understood that the methods described in this specification are described with reference to specific acts performed in accordance with a specific order, but it is to be understood that such acts may be combined, re-divided or reordered to form equivalent methods without departing from the teachings of the present invention. Therefore, the order and division of operations are not intended to limit the invention, unless specifically indicated to the contrary.

Claims (20)

Providing a wafer comprising a plurality of optical chips; Wherein each optical chip includes a plurality of pixels, each pixel including a lens,
Forming a lens protection layer on a lens of a pixel of the optical chip;
Separating the optical chip by cutting the wafer;
Disposing the separated optical chip on a substrate; And
And removing the lens protection layer from the lens of the pixel of the optical chip. The method according to claim 1,
Wherein forming the lens protection layer on the lens of the pixel of the optical chip comprises:
Forming a hydrophilic liquid protective material on a lens of a pixel of the optical chip; And
And a step of baking the hydrophilic liquid protective material to polymerize the hydrophilic liquid protective material to form a lens protective layer having hydrophobicity. 3. The method of claim 2,
Wherein the hydrophilic liquid protective material comprises polyurethane and 2-isopropoxyethanol. The method of claim 3,
Wherein the weight percentage of polyurethane is 60% to 80%, the weight percentage of 2-isopropoxy ethanol is 10% to 30%, and the weight percentage of polyurethane and 2-isopropoxy ethanol is 100% . 3. The method of claim 2,
Wherein the step of forming the hydrophilic liquid protective material on the lens of the pixel of the optical chip includes a spin-coating process, a spraying process, or an immersion process. 3. The method of claim 2,
Wherein the hydrophilic liquid protective material is formed on a lens of a pixel of an optical chip in a temperature range of 20 占 폚 to 30 占 폚. 3. The method of claim 2,
Wherein the temperature of the baking step is 100 占 폚 to 150 占 폚, and the time of the baking step is less than 10 minutes. The method according to claim 1,
Wherein removing the lens protection layer from the lens of the pixel of the optical chip comprises removing the lens protection layer using a chemical cleaning solution. 9. The method of claim 8,
Wherein the chemical cleaning solution has weak alkalinity. 9. The method of claim 8,
Wherein the chemical cleaning solution comprises dimethyl sulfoxide, diethylene glycol monobutyl ether, and polyoxyethylene polyoxypropylene polymer. 11. The method of claim 10,
The weight percent of dimethyl sulfoxide is 60% to 80%, the weight percentage of diethylene glycol monobutyl ether is 10% to 30%, the weight percentage of polyoxyethylene polyoxypropylene polymer is 1% to 5% Wherein the weight percentage of dimethyl sulfoxide, diethylene glycol monobutyl ether and polyoxyethylene polyoxypropylene polymer is 100% or less. 10. The method of claim 9,
Wherein removing the lens protective layer using the chemical cleaning solution comprises spraying a chemical cleaning solution onto the lens protective layer or immersing the lens protective layer in a chemical cleaning solution. 10. The method of claim 9,
Wherein the temperature of removing the lens protecting layer using the chemical cleaning solution is 20 to 30 占 폚 and the time of removing the lens protecting layer using the chemical cleaning solution is 30 to 120 seconds. The method according to claim 1,
Further comprising advancing a cleaning process on the wafer before the step of forming the lens protection layer on the lens of the pixel of the optical chip and after the step of removing the lens protection layer from the lens of the pixel of the optical chip, Way. The method according to claim 1,
Wherein the thickness of the lens protective layer is less than 10 microns. A plurality of pixels including an optical member;
A lens provided on the optical member; And
And a plurality of lens protective layers respectively provided on the lens. 17. The method of claim 16,
Wherein the optical member includes a photosensitive member. 17. The method of claim 16,
And a color filter provided between the optical member and the lens. 17. The method of claim 16,
Wherein the thickness of the lens protective layer is less than 10 microns. 17. The method of claim 16,
Wherein the lens protective layer is hydrophobic.

Images