JP2011088409A - Mold of wafer level lens array, manufacturing method of wafer level lens array, wafer level lens array, lens module, and imaging unit - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a mold of wafer level lens array capable of preventing the intrusion of air into a substrate and a lens to be molded, a method for manufacturing a wafer level lens array, a wafer level lens array, a lens module, and an imaging unit. <P>SOLUTION: A mold for molding integrally a wafer level lens array comprising a substrate and a plurality of lenses arranged on the substrate formed of resin has a pair of die materials for molding and curing the resin by sandwiching the resin and giving energy to the resin where an air discharging hole for discharging air in an interface between a die surface and a resin surface upon molding is formed in at least a die surface contacting with the resin. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a wafer level lens array mold, a wafer level lens array manufacturing method, a wafer level lens array, a lens module, and an imaging unit.

  In recent years, portable terminals of electronic devices such as mobile phones and PDAs (Personal Digital Assistants) are equipped with small and thin imaging units. Such an imaging unit generally includes a solid-state imaging device such as a CCD (Charge Coupled Device) image sensor or a CMOS (Complementary Metal-Oxide Semiconductor) image sensor, a lens for forming a subject image on the solid-state imaging device, It has.

  With the downsizing and thinning of portable terminals, there is a demand for downsizing and thinning of imaging units. Moreover, in order to reduce the cost of the portable terminal, it is desired to increase the efficiency of the manufacturing process. As a method for manufacturing such a small and many lenses, a wafer level lens array having a configuration in which a plurality of lens portions are formed on a substrate portion is manufactured, and the plurality of lenses are separated by cutting the substrate portion. Thus, a method for mass-producing lens modules is known.

  In addition, the substrate portion on which the plurality of lens portions are formed and the semiconductor wafer on which the plurality of solid-state image sensors are formed are combined together, and the semiconductor wafer is cut together with the substrate portion so as to include the lens portions and the solid-state image sensors as a set. Thus, a method of mass-producing imaging units is known.

Conventionally, as a method for manufacturing a wafer level lens, for example, there is an example of manufacturing a wafer level lens array by the following process. As such a manufacturing method, there is one shown in Patent Document 1 below.
(1) With the resin applied on the wafer, the shape of one transfer body (mold) is transferred to the resin.
(2) The process of transferring the shape of the mold is repeated about 1500 to 2400 times to form a master lens array having 1500 to 2400 lens shapes on one wafer.
(3) A stamper (Ni electroforming mold) is manufactured by depositing metal ions such as Ni on the lens surface of the master lens array by electroforming.
(4) A stamper is used as a pair of lens array molds, and a photocurable resin or a thermosetting resin is supplied to the lower mold member of the pair of lens array molds.
(5) The supplied resin is pressed by a lens array molding die of the upper mold member to deform the resin following the molding surfaces of the upper mold member and the lower mold member.
(6) The lens array is formed by irradiating the resin with light or heat and curing it.

  Patent Document 2 relates to an apparatus for transferring a fine pattern onto a photocurable resin by pressing a stamper on the photocurable resin in a vacuum state.

International Publication No. 2008/153102 JP 2003-94445 A

When the substrate portion and the lens portion are integrally molded with the same material as in Patent Document 1, there is a concern that air may be mixed into the molding material when the molding material is supplied to the mold. FIG. 21A and FIG. 22A show a state in which the resin 10R that is a molding material is sandwiched between the lower mold member M1 and the upper mold member M2. 21B and 22B show an example of the configuration of a wafer level lens formed by the lower mold member M1 and the upper mold member M2. 21A and 21B show a case where a lens having a convex surface is molded. 22A and 22B show a case where a lens having a concave surface is molded.
As shown in FIG. 21A and FIG. 22A, a predetermined amount of resin is supplied to the lower mold member M1, and then the resin is sandwiched between the lower mold member M1 and the upper mold member M2, and the resin is inserted into the lower mold member M1 and the upper mold member. The lens shape formed on the surface of M2 is deformed following a concave portion or convex portion for transferring. At this time, in the recesses on the surfaces of the molds M1 and M2 that are in contact with the resin, when the resin is sandwiched, air stays and it is difficult to escape from between the molds M1 and M2. If air remains inside the recess, when the resin is deformed, it tends to be mixed into the resin as indicated by A in the figure. When air is mixed in the resin, as shown in FIGS. 21B and 22B, a defect E such as a cavity or deformation occurs in the portion where the air is mixed in the lens portion of the molded wafer level lens. It is inevitable that the optical function will be affected.

  In addition, as in Patent Document 2, when the substrate portion and the lens portion are integrally formed in a vacuum, an increase in the size of the apparatus is inevitable. In addition, there is a disadvantage that it takes time to evacuate the chamber and the process time becomes long. In addition, since the resin is exposed to a vacuum atmosphere, the volatile components in the resin material may volatilize and the characteristics of the resin may change.

  The present invention relates to a wafer level lens array molding die capable of preventing air from being mixed into a molded substrate portion or lens portion when molding a wafer level lens array in which a substrate portion and a lens portion are integrated. A lens array manufacturing method, a wafer level lens array, a lens module, and an imaging unit are provided.

The present invention is a molding die for integrally molding a wafer level lens array comprising a substrate portion and a plurality of lens portions arranged on the substrate portion with a resin,
The mold comprises a pair of mold members that mold and cure the resin by sandwiching the resin and applying energy, and on the mold surface that contacts the resin of at least one mold member of the pair of mold members, This is a mold for a wafer level lens array provided with an air vent hole for exhausting air existing at the interface between the mold surface and the resin during molding.

  In this mold, air can be discharged to the outside of the mold through the air vent hole when the resin is sandwiched at the time of molding. Therefore, the air staying at the interface between the mold surface and the resin is discharged to the outside of the mold. Easy to remove. Air can be prevented from remaining inside the resin by the air vent hole, and air can be prevented from being mixed into the resin. For this reason, it is suitable for molding a wafer level lens having a good optical function in which the lens portion does not have a defect due to air mixing.

Further, the present invention is a manufacturing method for integrally molding a wafer level lens array comprising a substrate portion and a plurality of lens portions arranged on the substrate portion with a resin,
It consists of a pair of mold members that mold and cure the resin by sandwiching the resin and applying energy, and an air vent hole is provided on the mold surface of at least one mold member of the pair of mold members in contact with the resin The method of manufacturing a wafer level lens array, wherein when the mold surface of the mold is pressed against the resin, the resin is deformed while air is released to the outside from the air vent hole.

  Since this manufacturing method performs a process of discharging air staying between the mold surface and the resin from the mold air vent hole to the outside of the mold during molding, it is possible to prevent the air from being mixed into the resin. For this reason, it is possible to obtain a wafer level lens having a good optical function in which the lens portion does not have a defective portion due to air contamination.

Further, the mold for forming the wafer level lens array includes a peripheral portion in which the lens portion protrudes around the lens surface in the same direction as the lens surface, and at least one concave portion of the mold surface corresponding to the peripheral portion. It is preferable that the air vent hole is provided. Alternatively, the lens portion includes a peripheral portion that protrudes in a direction opposite to the lens surface around the lens surface, and at least one air vent hole is provided in the concave portion of the mold surface corresponding to the peripheral portion. A configuration is preferable.
Here, the peripheral portion is a portion that forms a flange portion or a spacer provided around the lens portion, or a portion that is provided thicker than the lens portion in order to ensure the thickness of the lens in the central portion of the biconcave lens. is there.
The flange prevents the lens functional surface from being touched or damaged when handling the lens. Further, when the lens is incorporated into the lens barrel, it functions as a portion that is positioned and held in the lens barrel. In the state of the wafer level lens array, the substrate portion remaining around the lens functions as a flange when the substrate is cut at the substrate portion even when it is not formed on the convex portion.
The spacer is a lens (optical system) for securing an interval between the lenses when the optical system is constituted by a plurality of lenses, or when the lens (optical system) and the photoelectric conversion element are integrated into a module. It is a member for ensuring the space between the photoelectric conversion element and the like, and may be provided integrally around the lens.
By providing at least one air vent hole in the concave portion of the mold surface corresponding to the peripheral portion, it is possible to prevent air bubbles from being mixed into the concave portion of the mold surface for forming the flange portion and the spacer around the lens. This also has the effect of preventing defects in the shape of the spacers.

  According to the present invention, a wafer level lens array molding die, a wafer level lens array manufacturing method, a wafer level lens array, a lens module, and an imaging unit that can prevent air from being mixed into a molded substrate portion or lens portion. Can be provided.

It is a top view which shows an example of a structure of a wafer level lens array. FIG. 2 is a cross-sectional view taken along line AA of the configuration of the wafer level lens array shown in FIG. 1. It is sectional drawing which shows an example of a structure of a lens module. It is sectional drawing which shows an example of a structure of an imaging unit. 5A to 5D are diagrams illustrating a procedure for manufacturing a mold for molding a lens portion on a substrate portion. 6A to 6C are diagrams illustrating a procedure for molding a resin as a molding material with a molding die. FIGS. 7A to 7C are diagrams illustrating a state where a cutting process or a light shielding process for removing the protrusions of the molded wafer level lens array is performed. 8A to 8C are examples of molding other wafer level lens arrays, and are diagrams illustrating a procedure of molding a resin as a molding material with a mold. 9A and 9B are diagrams for explaining a state in which a cutting process or a light shielding process is performed on the molded wafer level lens array. It is a figure which shows an example of a structure of the lens part of the shape | molded wafer level lens array, and the air vent hole of a type | mold member. It is a figure which shows the other example of a structure of the lens part of the shape | molded wafer level lens array, and the air vent hole of a type | mold member. It is a figure which shows the other example of a structure of the lens part of the shape | molded wafer level lens array, and the air vent hole of a type | mold member. It is a figure which shows the other example of a structure of the lens part of the shape | molded wafer level lens array, and the air vent hole of a type | mold member. It is a figure which shows the diameter of the recessed part of a type | mold member, and the diameter of an air vent hole. It is a figure which shows an example of the process given to an air vent hole. 16A and 16B are diagrams illustrating a process of dicing the wafer level lens array. 17A and 17B are diagrams illustrating a procedure of a manufacturing method of the lens module. It is a figure which shows another example of the procedure which manufactures a lens module. 19A and 19B are diagrams illustrating a procedure for manufacturing the imaging unit. 20A and 20B are diagrams illustrating another example of the procedure for manufacturing the imaging unit. 21A shows a procedure for molding a resin with a pair of mold members, and 21B shows a state of a cured wafer level lens array. 22A shows a procedure for molding a resin with a pair of mold members, and 22B shows a state of a cured wafer level lens array.

  First, the configuration of the wafer level lens array, the lens module, and the imaging unit will be described.

FIG. 1 is a plan view showing an example of the configuration of a wafer level lens array. FIG. 2 is a cross-sectional view taken along line AA of the configuration of the wafer level lens array shown in FIG.
The wafer level lens array includes a substrate unit 1 and a plurality of lens units 10 arranged on the substrate unit 1. The plurality of lens units 10 are arranged one-dimensionally or two-dimensionally with respect to the substrate unit 1. In this configuration example, as illustrated in FIG. 1, a configuration in which a plurality of lens units 10 are two-dimensionally arranged with respect to the substrate unit 1 will be described as an example. The lens unit 10 is made of the same material as the substrate unit 1 and is integrally formed with the substrate unit 1. The shape of the lens unit 10 is not particularly limited, and can be appropriately changed depending on the application.

  On one surface of the substrate portion 1, a spacer 12 may be provided for securing a space when overlapping with another member. The spacer 12 is a lattice-shaped member when the substrate unit 1 is viewed in a plan view with the spacer 12 attached to the substrate unit 1. The spacer 12 is, for example, a wall-like member extending perpendicularly to the surface of the substrate unit 1, and is provided so as to surround a part or all of the periphery of the lens unit 10.

FIG. 3 is a cross-sectional view showing an example of the configuration of the lens module.
The lens module includes a substrate unit 1 and a lens unit 10 formed integrally with the substrate unit 1. For example, the substrate unit 1 of the wafer level lens array shown in FIGS. 1 and 2 is diced. Those separated for each lens unit 10 are used. The spacers 12 are located at the dicing boundaries, are separated simultaneously by dicing, and are attached to the substrate portion 1 of each lens module.

FIG. 4 is a cross-sectional view illustrating an example of the configuration of the imaging unit.
The imaging unit includes the lens module described above and a sensor module. The lens unit 10 of the lens module forms a subject image on the solid-state imaging device D provided on the sensor module side. The substrate portion 1 of the lens module and the semiconductor substrate W of the sensor module are formed in a substantially rectangular shape in plan view so as to be substantially the same.

  The sensor module includes a semiconductor substrate W and a solid-state imaging device D provided on the semiconductor substrate W. The semiconductor substrate W is formed by cutting a wafer formed of a semiconductor material such as silicon into a substantially rectangular shape in plan view. The solid-state image sensor D is provided at a substantially central portion of the semiconductor substrate W. The solid-state image sensor D is, for example, a CCD image sensor or a CMOS image sensor. The sensor module can have a configuration in which a solid-state imaging device D that is made into a chip is bonded onto a semiconductor substrate on which wirings and the like are formed. Alternatively, the solid-state imaging device D is configured by repeating a well-known film forming process, photolithography process, etching process, impurity adding process, and the like on the semiconductor substrate W, and forming electrodes, insulating films, wirings, and the like on the semiconductor substrate. May be.

  In the lens module, the substrate portion 1 is superimposed on the semiconductor substrate W of the sensor module with the spacer 12 interposed therebetween. The spacer 12 of the lens module and the semiconductor substrate W of the sensor module are bonded using, for example, an adhesive. The spacer 12 is designed so that the lens unit 10 of the lens module forms a subject image on the solid-state imaging device D of the sensor module, and the lens unit 10 and the solid-state imaging are so arranged that the lens unit 10 does not contact the sensor module. It is formed with a thickness separating a predetermined distance from the element D.

  The shape of the spacer 12 is not particularly limited as long as the spacer 12 can maintain a positional relationship with a predetermined distance between the substrate portion 1 of the lens module and the semiconductor substrate W of the sensor module, and the spacer 12 can be appropriately modified. For example, the spacers 12 may be columnar members provided at the four corners of the substrate. The spacer 12 may be a frame-shaped member that surrounds the solid-state imaging device D of the sensor module. If the solid-state image pickup device D is isolated from the outside by being surrounded by the frame-shaped spacer 12, the solid-state image pickup device D can be shielded from light other than the light passing through the lens. Moreover, it can prevent that dust adheres to the solid-state image sensor D by sealing the solid-state image sensor D from the outside.

  The lens module shown in FIG. 3 is configured to include one substrate unit 1 on which the lens unit 10 is formed, but may be configured to include a plurality of substrate units 1 on which the lens unit 10 is formed. At this time, the substrate portions 1 that are overlapped with each other are assembled together via the spacers 12.

  Alternatively, an imaging unit may be configured by joining a sensor module via a spacer 12 to the lowermost substrate portion 1 of the lens module including a plurality of substrate portions 1 on which the lens portions 10 are formed. A lens module including a plurality of substrate units 1 on which the lens unit 10 is formed and a method for manufacturing an imaging unit including the lens module will be described later.

  The imaging unit configured as described above is reflow-mounted on a circuit board (not shown) built in a portable terminal or the like. The circuit board is preliminarily printed with paste-like solder at a position where the imaging unit is mounted, and the imaging unit is mounted on the circuit board. The circuit board including the imaging unit is irradiated with infrared rays or hot air is blown. Heat treatment is performed, and the imaging unit is welded to the circuit board.

  The energy curable resin composition used in the wafer level lens array of the present invention is either a resin composition that is cured by heat or a resin composition that is cured by irradiation with active energy rays (for example, ultraviolet rays or electron beam irradiation). There may be.

  From the viewpoint of moldability such as mold shape transfer suitability, it is preferable that the resin has appropriate fluidity before curing. Specifically, it is liquid at room temperature and has a viscosity of about 1000 to 50000 mPa · s.

  On the other hand, it is preferable to have heat resistance that does not cause thermal deformation even after the reflow process after curing. From this viewpoint, the glass transition temperature of the cured product is preferably 200 ° C. or higher, more preferably 250 ° C. or higher, and particularly preferably 300 ° C. or higher. In order to impart such high heat resistance to the resin composition, it is necessary to constrain the mobility at the molecular level, and as effective means, (1) means for increasing the crosslinking density per unit volume, (2) Means utilizing a resin having a rigid ring structure (for example, an alicyclic structure such as cyclohexane, norbornane, tetracyclododecane, an aromatic ring structure such as benzene and naphthalene, a cardo structure such as 9,9′-biphenylfluorene, Resins having a spiro structure such as spirobiindane, specifically, for example, JP-A-9-137043, JP-A-10-67970, JP-A-2003-55316, JP-A-2007-334018, JP-A-2007-238883 (3) means for uniformly dispersing a high Tg substance such as inorganic fine particles (for example, JP-A-5-20 027, JP-described), and the like in the 10-298265 Patent Publication. A plurality of these means may be used in combination, and it is preferable to make adjustments within a range that does not impair other characteristics such as fluidity, shrinkage rate, and refractive index characteristics.

  From the viewpoint of shape transfer accuracy, a resin composition having a small volume shrinkage due to the curing reaction is preferable. The curing shrinkage rate of the resin composition used in the present invention is preferably 10% or less, more preferably 5% or less, and particularly preferably 3% or less.

  Examples of the resin composition having a low curing shrinkage rate include (1) resin compositions containing a high molecular weight curing agent (such as a prepolymer) (for example, JP-A Nos. 2001-19740, 2004-302293, and 2007). No. -21247, etc., the number average molecular weight of the high molecular weight curing agent is preferably in the range of 200 to 100,000, more preferably in the range of 500 to 50,000, particularly preferably 1,000 to. The value calculated by the number average molecular weight of the curing agent / the number of curing reactive groups is preferably in the range of 50 to 10,000, and in the range of 100 to 5,000. (2) a tree containing a non-reactive substance (organic / inorganic fine particles, non-reactive resin, etc.). Fat composition (for example, described in JP-A-6-298883, JP-A-2001-247793, JP-A-2006-225434, etc.), (3) Resin composition containing a low-shrinkage crosslinking reactive group (for example, ring-opening) A polymerizable group (for example, an epoxy group (for example, described in JP-A No. 2004-210932), an oxetanyl group (for example, described in JP-A No. 8-134405), an episulfide group (for example, JP-A No. 2002-105110) ), Cyclic carbonate groups (for example, described in JP-A-7-62065, etc.), ene / thiol curing groups (for example, described in JP-A 2003-20334), hydrosilylation curing groups (for example, (4) a tree containing a rigid skeleton resin (fluorene, adamantane, isophorone, etc.) Composition (for example, described in JP-A-9-137043), (5) a resin composition containing two types of monomers having different polymerizable groups and forming an interpenetrating network structure (so-called IPN structure) (for example, (Described in JP-A-2006-131868, etc.), (6) resin compositions containing expandable substances (for example, described in JP-A-2004-2719, JP-A-2008-238417, etc.) In addition, the present invention can be suitably used in the present invention, and the physical properties include the use of a plurality of curing shrinkage reducing means described above (for example, a prepolymer containing a ring-opening polymerizable group and fine particles). It is preferable from the viewpoint of optimization.

For the wafer level lens array of the present invention, two or more types of resin compositions having different Abbe numbers are desired.
The resin on the high Abbe number side preferably has an Abbe number (νd) of 50 or more, more preferably 55 or more, and particularly preferably 60 or more. The refractive index (nd) is preferably 1.52 or more, more preferably 1.55 or more, and particularly preferably 1.57 or more.
Such a resin is preferably an aliphatic resin, particularly a resin having an alicyclic structure (for example, a resin having a cyclic structure such as cyclohexane, norbornane, adamantane, tricyclodecane, tetracyclododecane, specifically, for example, JP-A-10-152551, JP-A-2002-212500, JP-A-2003-20334, JP-A-2004-210932, JP-2006-199790, JP-2007-2144, JP-2007-284650. And the resin described in JP-A-2008-105999.

The resin on the low Abbe number side preferably has an Abbe number (νd) of 30 or less, more preferably 25 or less, and particularly preferably 20 or less. The refractive index (nd) is preferably 1.60 or more, more preferably 1.63 or more, and particularly preferably 1.65 or more.
As such a resin, a resin having an aromatic structure is preferable. For example, a resin having a structure such as 9,9′-diarylfluorene, naphthalene, benzothiazole, benzotriazole and the like (specifically, for example, JP-A-60-38411). Publication No. 10-67977, No. 2002-47335, No. 2003-238842, No. 2004-83855, No. 2005-325331, No. 2007-238883, International Publication 2006. / 095610 publication, Japanese Patent No. 2537540 publication, etc.) are preferable.

In the resin of the present invention, inorganic fine particles are preferably dispersed in a matrix for the purpose of increasing the refractive index and adjusting the Abbe number. Examples of the inorganic fine particles include oxide fine particles, sulfide fine particles, selenide fine particles, and telluride fine particles. More specifically, for example, fine particles of zirconium oxide, titanium oxide, zinc oxide, tin oxide, niobium oxide, cerium oxide, aluminum oxide, lanthanum oxide, yttrium oxide, zinc sulfide, and the like can be given.
In particular, it is preferable to disperse fine particles such as lanthanum oxide, aluminum oxide, and zirconium oxide for the high Abbe number resin, and titanium oxide, tin oxide, zirconium oxide, and the like for the low Abbe number resin. The fine particles are preferably dispersed. The inorganic fine particles may be used alone or in combination of two or more. Moreover, the composite by several components may be sufficient. In addition, for various purposes such as reducing photocatalytic activity and water absorption, the inorganic fine particles are doped with different metals, the surface layer is coated with different metal oxides such as silica and alumina, silane coupling agents and titanate cups. The surface may be modified with a ring agent, an organic acid (carboxylic acid, sulfonic acid, phosphoric acid, phosphonic acid, etc.) or a dispersant having an organic acid group. The number average particle size of the inorganic fine particles is usually about 1 nm to 1000 nm, but if it is too small, the properties of the substance may change. If it is too large, the influence of Rayleigh scattering becomes remarkable, so 1 nm to 15 nm is preferable. 2 nm to 10 nm are more preferable, and 3 nm to 7 nm are particularly preferable. Further, it is desirable that the particle size distribution of the inorganic fine particles is narrow. There are various ways of defining such monodisperse particles. For example, a numerical value range as described in JP-A No. 2006-160992 applies to a preferable particle size distribution range. Here, the above-mentioned number average primary particle size can be measured by, for example, an X-ray diffraction (XRD) apparatus or a transmission electron microscope (TEM). The refractive index of the inorganic fine particles is preferably 1.90 to 3.00, more preferably 1.90 to 2.70, and more preferably 2.00 to 2.70 at 22 ° C. and a wavelength of 589 nm. It is particularly preferred that The content of the inorganic fine particles with respect to the resin is preferably 5% by mass or more, more preferably 10 to 70% by mass, and particularly preferably 30 to 60% by mass from the viewpoint of transparency and high refractive index.

  In order to uniformly disperse the fine particles in the resin composition, for example, a dispersant containing a functional group having reactivity with a resin monomer that forms a matrix (for example, described in Examples of JP 2007-238884 A), hydrophobic Block copolymer composed of a functional segment and a hydrophilic segment (for example, described in JP-A-2007-2111164), or having a functional group capable of forming an arbitrary chemical bond with inorganic fine particles at the polymer terminal or side chain It is desirable to disperse the fine particles by appropriately using a resin (for example, described in JP 2007-238929 A, JP 2007-238930 A, etc.).

  In addition, the resin composition to be used in the present invention appropriately contains additives such as known release agents such as silicon-based, fluorine-based, and long-chain alkyl group-containing compounds and antioxidants such as hindered phenols. May be.

  If necessary, the curable resin composition of the present invention may contain a curing catalyst or an initiator. Specifically, for example, a compound that accelerates a curing reaction (radical polymerization or ionic polymerization) by the action of heat or active energy rays described in JP-A-2005-92099 (paragraph numbers [0063] to [0070]). Can be mentioned. The amount of these curing reaction accelerators to be added varies depending on the type of catalyst and initiator, or the difference in the curing reactive site, and cannot be specified unconditionally, but in general, the total solid content of the curing reactive resin composition About 0.1-15 mass% is preferable with respect to a minute, and about 0.5-5 mass% is more preferable.

  The curable resin composition of the present invention can be produced by appropriately blending the above components. At this time, if other components can be dissolved in the liquid low molecular weight monomer (reactive diluent), etc., it is not necessary to add a separate solvent, but if this is not the case, use a solvent. A curable resin composition can be produced by dissolving each component. The solvent that can be used in the curable resin composition is not particularly limited as long as the composition is uniformly dissolved or dispersed without precipitation, and specifically, for example, Ketones (eg, acetone, methyl ethyl ketone, methyl isobutyl ketone, etc.), esters (eg, ethyl acetate, butyl acetate, etc.), ethers (eg, tetrahydrofuran, 1,4-dioxane, etc.) Alcohols (eg, methanol, ethanol) Isopropyl alcohol, butanol, ethylene glycol, etc.), aromatic hydrocarbons (eg, toluene, xylene, etc.), water and the like. When the curable composition contains a solvent, it is preferable to perform a mold shape transfer operation after casting the composition on a substrate and / or a mold and drying the solvent.

Next, a manufacturing method of the wafer level lens array will be described in detail.
5A to 5D are diagrams illustrating a procedure for manufacturing a mold for forming a lens portion on a substrate portion.
As shown in FIG. 5A, the replica lens 22 is molded by transferring the mold surface of the core 23 onto an ultraviolet curable resin (acrylic or epoxy) on a glass substrate 21 and irradiating with ultraviolet rays. Thus, as shown in FIG. 5B, a master lens array simulating the shape of a desired lens array in which a plurality of replica lenses 22 are arranged on the glass substrate 21 is created.

  Next, as shown in FIG. 5C, a metal ion such as nickel (Ni) is deposited on the lens surface of the master lens array by electroforming to manufacture a stamper (Ni electroforming mold) 102.

  As seen in FIG. 5D, the stamper 102 peeled from the master lens array is provided with a lens transfer portion 102a. In this example, the lens transfer portion 102a has a shape corresponding to the shape of the concave portion, that is, the convex lens portion, but may have a shape corresponding to the shape of the concave or aspherical lens portion. The mold used in the manufacturing process described below is not particularly limited to this stamper 102.

  As shown in FIG. 5D, when the curved concave portion is used as the lens transfer portion 102a, the air vent hole V1 is formed at the most depressed position of the concave portion.

  6A to 6C show a procedure for molding a resin as a molding material with a molding die. In the following description, the stamper 102 is also referred to as a mold or a mold. For the configuration of the wafer level lens array, the structure shown in FIG.

  Here, two molds are prepared, one mold being the lower mold member 102 and the other mold being the upper mold member 104. Air vent holes V1 and V2 are provided in lens transfer portions 102a and 104a, which are concave portions of the lower mold member 102 and the upper mold member 104, respectively. First, the resin 10R is supplied to the mold surface of the lower mold member 102 provided with the lens transfer portion 102a. The resin 10R will be described using an ultraviolet curable resin, but may be a thermosetting resin.

  After the resin 10R is supplied to the lower mold member 102, the upper mold member 104 is lowered. Then, as seen in FIG. 6B, the mold surface provided with the lens transfer portion 104a of the upper mold member 104 is brought into contact with the resin 10R. Air is contained between the lens transfer portion 104a of the upper mold member 104 and the surface of the resin 10R. This air is guided to the air vent hole V2 formed in the lens transfer portion 104a by the pressure of the resin 10R by sandwiching the resin 10R between the lower mold member 102 and the upper mold member 104, and the air vent hole V2 is passed through the air vent hole V2. It is discharged from the lower mold member 102 and the upper mold member 104.

  As shown in FIG. 6C, the upper mold member 104 and the lower mold member 102 are brought close to each other until a predetermined distance is reached. While the upper mold member 104 and the lower mold member 102 are brought close to each other, the air is continuously discharged from the air vent hole V2 until there is no air remaining in the lens transfer portion 104a. After the movement of the upper mold member 104 and the lower mold member 102 is stopped and the air is completely removed, the resin 10R is cured while the upper mold member 104 and the lower mold member 102 are closed by irradiating ultraviolet rays. After curing, the molded wafer level lens array is taken out from the lower mold member 102 and the upper mold member 104.

  The cross-sectional shape of the air vent holes V1 and V2 is not limited, but if it is circular, the machining operation is easy when machining the holes. The air vent holes V1 and V2 function as air vent holes as long as they communicate with the outside at portions other than the mold surfaces of the mold members 102 and 104. However, the air vent holes V1 and V2 are linearly provided in the mold members 102 and 104. It is preferable to do. This facilitates the passage of air and facilitates the process of extracting air, which will be described later. Further, it is preferable that the air vent holes V1 and V2 communicate with the surface opposite to the mold surface on which the lens transfer portions 102a and 104a are provided. In this way, the air staying in the concave portions of the lens transfer portions 102a and 104a can be smoothly extracted through the air vent holes V1 and V2.

  Further, the air vent holes V1 and V2 may communicate with an air discharge path connected to a suction device (not shown). If it carries out like this, discharge | emission of air can be accelerated | stimulated by attracting | sucking air through the air discharge path from the recessed part side of a lens transfer part with a suction device.

FIGS. 7A to 7C are views for explaining a state in which a cutting process or a light shielding process for removing the protrusions of the molded wafer level lens array is performed.
It is conceivable that a part of the resin 10R enters the air vent holes V1 and V2 and is cured as it is. Then, as shown in FIG. 7A, a part of the resin cured in the air vent holes V1 and V2 may remain as protrusions in the lens portion of the released wafer level lens array. Such protrusions can be removed by a cutting process.

  FIG. 7B shows a procedure for removing the protrusion 10X formed on the lens portion 10 of the wafer level lens array of FIG. 7A by a cutting process. In the cutting process, the protruding part 10 </ b> X is removed by performing a cutting process on a cutting surface parallel to the surface of the substrate unit 1. In the cutting process, the protrusion 10X of each lens unit 10 can be simultaneously removed by a cutting member having a blade parallel to the cutting surface. At this time, a part of the top of the convex surface of the lens unit 10 may be cut together with the protrusion 10X, and the flat part 10F may be formed on the top of the lens unit 10. The flat portion 10F is formed concentrically with respect to the optical axis when viewed from the optical axis side of the lens portion 10. If the flat portion 10F has a sufficiently small area, the influence on the optical performance of the lens portion 1 can be reduced.

  Further, as seen in FIG. 7C, after removing the protrusion 10X of the lens unit 10, a light shielding process may be performed on the part where the protrusion 10X is formed. As the light shielding process, for example, a black light shielding layer is applied to the surface of the portion where the protrusion 10X of the lens unit 10 is formed. As a material for the light shielding layer, a material that can absorb incident light without allowing it to pass therethrough is used.

  Since the portion where the light shielding layer of the lens unit 10 is formed shields incident light, when a wafer level lens array is applied to the imaging module, a black dot-like shadow is imaged on the image corresponding to the position of the light shielding layer. It is possible. In this case, the shadow portion may be corrected by image processing.

  In the above procedure, the wafer level lens array having a shape in which the lens portion includes a convex surface protruding from the substrate portion 1 has been described as an example. However, the shape of the lens portion of the wafer level lens array to be molded is not limited to this.

  FIGS. 8A to 8C are diagrams illustrating an example of molding another wafer level lens array and illustrating a procedure of molding a resin as a molding material with a mold. This wafer level lens array has a configuration in which the lens portion includes a concave surface that is recessed toward the substrate portion 1 and a peripheral portion that protrudes from the surface of the substrate portion 1 around the concave surface.

As shown in FIG. 8A, the lower mold member 202 and the upper mold member 204 are provided with a plurality of recesses for transferring the lens section on the surface in contact with the resin 10R.
The concave portion of the lower mold member 202 includes a lens transfer portion 202a for transferring the concave surface to the lens portion, and a lens peripheral transfer portion 202b for transferring the shape of the peripheral portion provided around the concave surface of the lens portion. Similarly, the concave portion of the upper mold member 204 includes a lens transfer portion 204a for transferring the concave surface to the lens portion, and a lens peripheral transfer portion 204b for transferring the shape of the peripheral portion provided around the concave surface of the lens portion. including.
In the lower mold member 202 and the upper mold member 204, since the lens peripheral transfer portions 202b and 204b are deeper than the surface in contact with the resin 10R, it is considered that air tends to stay when pressed against the resin 10R. . For this reason, in this example, air vent holes V1 and V2 are formed in portions corresponding to the lens peripheral transfer portions 202b and 204b in the concave portion.

  As a molding procedure, first, as shown in FIG. 8A, the resin 10R is supplied to the surface of the lower mold member 202 provided with the recesses, and the upper mold member 204 is lowered.

  As shown in FIG. 8B, when the upper mold member 204 is lowered, the lens transfer portion 204a first contacts the resin 10R. When the upper mold member 204 is further lowered, the air between the surface of the resin 10R and the lens peripheral transfer portion 204b is guided to the air vent hole V2 by the pressure of the resin 10R, and passes through the air vent hole V2 to the outside. Discharged.

  As shown in FIG. 8C, the upper mold member 204 and the lower mold member 202 are brought close to each other until a predetermined distance is reached. While the upper mold member 204 and the lower mold member 202 are brought close to each other, the air is continuously discharged from the air vent hole V2 until there is no air remaining in the lens periphery transfer portion 204b. After the movement of the upper mold member 204 and the lower mold member 202 is stopped and the air is completely removed, the resin 10R is cured while the upper mold member 204 and the lower mold member 202 are closed by irradiating ultraviolet rays. After curing, the molded wafer level lens array is taken out from the lower mold member 202 and the upper mold member 204.

  Regardless of the shape of the lens portion, air can be smoothly discharged by providing the air vent hole so as to open at the most depressed position among the concave portions for transferring the lens portion. Further, depending on the shape of the lens part, it is preferable to provide an air vent hole in the mold surface in contact with the resin including the most depressed position among the concave parts of the mold member.

FIG. 9A is a diagram showing a state of the wafer level lens array formed by the procedure of FIGS. 8A to 8C.
In the wafer level lens array, a protrusion X is formed on the lens peripheral portion 20b. In the shape of the lens portion 20, since the concave surface 20a functions as an optical surface, the projection 20X of the lens peripheral portion 20b has little influence on the optical performance. However, it is conceivable to remove the protrusion 20X for the reason of the appearance of the wafer level lens array, the reason for overlaying with a semiconductor wafer or another wafer level lens array, or other reasons.

FIG. 9B shows a procedure for removing the protrusion 20X formed on the lens unit 20 of the wafer level lens array of FIG. 9A by a cutting process. In the cutting process, the protruding part 20 </ b> X is removed by performing a cutting process on a cutting surface (indicated by a dotted line in the drawing) parallel to the surface of the substrate unit 1.
In addition, you may further perform the light-shielding process mentioned above to the site | part of the removed projection part 20X.

  The air vent hole is formed so as to open at the most depressed position of the recess according to the shape of the lens part to be molded. The shapes of the concave portion and the lens portion are not particularly limited and can be changed as appropriate.

FIG. 10 is a diagram showing an example of the configuration of the lens portion of the molded wafer level lens array and the air vent hole of the mold.
As shown in FIG. 10, the lens unit 10 has a non-curved surface shape including both a concave surface and a convex surface. The lens unit 10 has a shape including a concave surface formed on a concentric circle in the vicinity including the optical axis OS, and a convex surface 10a provided around the concave surface. Of the concave portion, the mold member 102 has the most concave portion where the convex surface 10a of the lens portion 10 is transferred, and a plurality of air vent holes V1 are provided in the portion. The plurality of air vent holes V1 are formed at substantially equal intervals in the circumferential direction of a circle centered on the optical axis OS. According to this configuration, since air in the concave portion of the mold member 102 is discharged through the air vent hole V1 during molding, deterioration of the optical performance of the molded lens unit 10 can be prevented.

FIG. 11 is a diagram showing another example of the configuration of the lens portion of the molded wafer level lens array and the air vent hole of the mold.
As shown in FIG. 11, the lens unit 10 has a non-curved surface shape including both a concave surface and a convex surface. The lens unit 10 includes a convex surface formed on a concentric circle in the vicinity including the optical axis OS, a concave surface 10a provided around the convex surface, and a lens peripheral portion 10c protruding from the surface of the substrate unit 1 around the concave surface 10a. It is a shape containing. In the mold member 102, a portion of the concave portion where the convex surface 10 b of the lens portion 10 is transferred is most recessed, and an air vent hole V <b> 1 is provided in the portion. An air vent hole V1 provided in a portion of the concave portion where the convex surface 10b of the lens unit 10 is transferred is provided so as to open at substantially the same position as the optical axis OS.

  Further, the lens peripheral transfer portion that transfers the shape of the lens peripheral portion 10 c constitutes a part of the concave portion provided on the mold surface of the substrate portion 1. The lens peripheral transfer portion is also provided with a plurality of air vent holes V1. The plurality of air vent holes V1 provided in the lens periphery transfer portion are formed at substantially equal intervals in the circumferential direction of a circle centered on the optical axis OS. According to this configuration, since air in the concave portion of the mold member 102 is discharged through the air vent hole V1 during molding, deterioration of the optical performance of the molded lens unit 10 can be prevented.

FIG. 12 is a diagram showing another example of the configuration of the lens portion of the molded wafer level lens array and the air vent hole of the mold.
As shown in FIG. 12, the lens portion 10 has a shape including both a convex surface 10d and a wall-shaped lens peripheral portion 10e substantially perpendicular to the substrate portion 1 around the convex surface 10d. Here, it is assumed that the heights of the convex surface 10d and the lens peripheral portion 10e from the substrate portion 1 are substantially equal. In the mold surface of the mold member 102, an air vent hole V1 is provided at a portion where the convex surface 10d of the lens unit 10 is transferred. An air vent hole V1 provided in a portion of the concave portion where the convex surface 10d of the lens portion 10 is transferred is provided so as to open at substantially the same position as the optical axis OS.

  Moreover, the lens periphery transfer part which transfers the shape of the lens periphery part 10e comprises a part of recessed part provided in the type | mold surface. The lens peripheral transfer portion is also provided with a plurality of air vent holes V1. The plurality of air vent holes V1 provided in the lens periphery transfer portion are formed at substantially equal intervals in the circumferential direction of a circle centered on the optical axis OS. According to this configuration, since air that has entered between the resin and the recess of the mold member 102 is discharged through the air vent hole V1 during molding, deterioration of the optical performance of the molded lens unit 10 can be prevented.

FIG. 13 is a diagram showing another example of the configuration of the lens portion of the molded wafer level lens array and the air vent hole of the mold.
As shown in FIG. 13, the lens unit 10 provided on one surface of the substrate unit 1 has a shape including a concave surface 10 f. The mold surface of the mold member 102 is provided with a convex portion that transfers the concave surface 10 f of the lens unit 10. An air vent hole V1 is provided in a flat portion where the convex portion of the mold surface is not provided. In this way, when the mold surface of the mold member 102 is pressed against the resin, the air accumulated between the convex portions can be discharged to the outside through the air vent hole V1.

  FIG. 14 is a diagram showing the diameter of the concave portion of the mold member and the diameter of the air vent hole. Here, the diameter of the recess provided in the mold member 102 is D1, and the diameter of the air vent hole V1 provided in the recess is D2. At this time, the diameter D2 of the air vent hole is preferably 1/10 or less of the diameter D1 of the recess. More preferably, the diameter D2 of the air vent hole is 1/20 or less of the diameter D1 of the recess.

  As shown in FIG. 13, when the concave portion is between the projections of the mold surface (for transferring the concave lens surface) and the air vent hole V1 is provided in the concave portion, the air vent hole V1 is the most. The sum d1 + d2 of the distance d1 between the outer edge of the close convex portion and the center of the air vent hole V1 and the distance d2 between the outer edge of the convex portion second closest to the air vent hole V1 and the center of the air vent hole V1 Let D1. In this case, when the diameter of the air vent hole V1 is D2, the diameter D2 is preferably 1/10 or less of D1 (d1 + d2), and more preferably 1/20 or less.

FIG. 15 is a diagram illustrating an example of processing performed on the air vent hole after molding.
It is conceivable that after molding, the resin as a molding material remains in the air vent hole V1 of the mold member 102 and closes the air vent hole V1 itself, so that it is difficult for air to escape during the next molding. The remaining resin may be removed by inserting a small-diameter member into the air vent hole V1. Alternatively, the remaining resin may be removed by injecting a treatment liquid or a solvent into the air vent hole V1. If it carries out like this, a type | mold can be used for repeated shaping | molding in a favorable state.

  Next, a procedure for manufacturing a lens module and an imaging unit using the wafer level lens array will be described.

16A and 16B are diagrams illustrating a process of dicing the wafer level lens array. A spacer 12 is provided on one surface (the lower surface in the figure) of the substrate unit 1 of the wafer level lens array.
As shown in FIG. 16B, alignment is performed between the substrate unit 1 of the wafer level lens array and the semiconductor substrate W formed in a wafer shape in the same manner as the substrate unit 1. At this time, a plurality of stacked wafer level lens arrays may be superimposed on the semiconductor substrate W. On one surface (the upper surface in the figure) of the semiconductor substrate W, the solid-state imaging device D is provided in the same arrangement as the arrangement of the plurality of lens units 10 provided on the substrate unit 1. Then, the substrate portion 1 of the wafer level lens array is superimposed on the semiconductor substrate W formed in a wafer shape similarly to the substrate portion 1 via the spacer 12 (see FIG. 14), and is integrally bonded. Thereafter, the integrated wafer level lens array and the semiconductor substrate W are cut using a cutting means such as a blade C along a cutting line defined between the arrays of the lens unit 10 and the solid-state imaging device D. And separated into a plurality of imaging units. The cutting line is, for example, in a lattice shape in plan view of the substrate unit 1.

  In this example, the description is given by taking an example of dicing when an imaging unit is manufactured. On the other hand, the dicing when manufacturing the lens module is not bonded to the semiconductor substrate W, but is cut according to the arrangement of the lens portions 10 and separated into a plurality of lens modules.

  17A and 17B are diagrams illustrating a procedure of a manufacturing method of the lens module. In this procedure, an example will be described in which a wafer level lens array in which a plurality of lens portions 10 are integrally formed on one substrate portion 1 is diced and separated into a plurality of lens modules.

  First, as shown in FIG. 17A, a wafer level lens array is prepared. The wafer level lens array can be manufactured by the procedure described above, and in the following description, the procedure is omitted without being described.

  Next, as shown in FIG. 17B, the substrate unit 1 of the wafer level lens array is cut along a cutting line indicated by a dotted line in the drawing, and separated into a plurality of lens modules. At this time, the spacers 12 positioned on each cutting line are also cut simultaneously. The spacer 12 is divided with each cutting line as a boundary, and is attached to each lens module adjacent to each cutting line. Thus, the lens module is completed.

  Note that the separated lens module may be assembled to a substrate including a sensor module (not shown) and other optical elements via the spacer 12.

  The spacer 12 may be integrally formed in advance on the substrate unit 1 of the wafer level lens array, and then the substrate unit 1 of the wafer level lens array together with the spacer 12 may be cut in a dicing process. By doing so, the lens modules can be mass-produced more efficiently than in the case where the spacers 12 are joined to the separated lens modules, and the productivity can be improved.

  FIG. 18 is a diagram showing another example of a procedure for manufacturing a lens module. In this procedure, an example will be described in which two substrate portions 1 and a wafer level lens array in which a plurality of lens portions 10 are integrally formed on each substrate portion 1 are diced and separated into a plurality of lens modules.

  First, as shown in FIG. 18, a plurality of wafer level lens arrays are prepared. The wafer level lens array can be manufactured by the procedure described above, and in the following description, the procedure is omitted without being described. A spacer 12 is formed on one surface of each substrate portion 1 of the plurality of wafer level lens arrays. Then, the substrate portions 1 of the wafer level lens array to be overlaid are aligned with each other, and the lower surface of the substrate portion 1 of the wafer level lens array to be overlaid is placed on the upper surface of the substrate portion 1 of the wafer level lens array to be placed below the spacer. 12 is joined. In a state where the wafer level lens arrays are overlapped with each other, the position of the spacer 12 with respect to each substrate unit 1 is set to be the same in each substrate unit 1.

  And the board | substrate part 1 of a wafer level lens array is cut | disconnected along the cutting line shown with a dotted line in a figure, and is isolate | separated into a some lens module. At this time, the spacers 12 at the overlapping positions on the respective cutting lines are also cut at the same time, and the spacers 12 divided with the respective cutting lines as boundaries are attached to the lens modules adjacent to the respective cutting lines. Thus, a lens module including a plurality of lens units 10 is completed. In this procedure, since the positions of the lens unit 10 and the spacer 12 with respect to the respective substrate units 1 to be overlaid are the same, the configurations of the plurality of separated lens modules are all the same. Further, the position of the cutting line may be determined based on the uppermost substrate portion 1 among the respective substrate portions 1 to be overlapped and cut.

  Note that the separated lens module may be assembled to a substrate including a sensor module (not shown) and other optical elements via the spacer 12.

  In this way, if a plurality of wafer level lens arrays are overlapped, and then the substrate part 1 of the wafer level lens array is cut together with the spacers 12 in the dicing process, compared to the case where the separated lens modules are individually overlapped. Thus, the lens module can be mass-produced efficiently, and the productivity is improved.

  19A and 19B are diagrams illustrating a procedure for manufacturing the imaging unit. In this procedure, an example will be described in which a single substrate unit 1 and a lens module in which a plurality of lens units 10 are integrally formed on the substrate unit 1 are joined to a sensor module and diced to be separated into a plurality of imaging units.

  First, as shown in FIG. 19A, a wafer level lens array is prepared. The wafer level lens array can be manufactured by the procedure described above, and in the following description, the procedure is omitted without being described. A spacer 12 is integrally formed on the lower surface of the substrate unit 1.

  Next, a semiconductor substrate W on which a plurality of solid-state imaging elements D are arranged is prepared. After aligning the substrate unit 1 of the wafer level lens array with the semiconductor substrate W, the substrate unit 1 is bonded to the upper surface of the semiconductor substrate W via the spacer 12. At this time, the extension of the optical axis of each lens unit 10 provided on the substrate unit 1 intersects with the central part of the solid-state imaging device D.

  Then, as shown in FIG. 19B, after joining the substrate unit 1 of the wafer level lens array and the semiconductor substrate W, the substrate unit 1 is cut along a cutting line indicated by a dotted line in the drawing, and a plurality of imaging units To separate. At this time, the spacers 12 positioned on each cutting line are also cut simultaneously. The spacer 12 is divided with each cutting line as a boundary, and is attached to each imaging unit adjacent to each cutting line. Thus, the imaging unit is completed.

  In this way, the spacer 12 is formed in advance on the wafer level lens array, and then the substrate of the wafer level lens array and the semiconductor substrate W provided with the solid-state imaging device D are overlapped to form the substrate unit 1 and the semiconductor substrate W. Can be mass-produced and produced more efficiently than in the case of manufacturing the imaging unit by joining the sensor module to the separated lens modules via the spacers 12, respectively. Can be improved.

  20A and 20B are diagrams illustrating another example of the procedure for manufacturing the imaging unit. In this procedure, two substrate portions 1 and a wafer level lens array in which a plurality of lens portions 10 are integrally formed on each substrate portion 1 are bonded to a semiconductor substrate provided with a solid-state imaging device, and each is dized. An example of separation into a plurality of imaging units including one lens unit 10 will be described.

  First, as shown in FIG. 20A, two wafer level lens arrays are prepared. The wafer level lens array can be manufactured by the procedure described above, and in the following description, the procedure is omitted without being described. A spacer 12 is formed in advance on the lower surface of each of the two substrate portions 1 to be superimposed. Then, the substrate portions 1 of the wafer level lens array to be superimposed are aligned with each other, and the lower surface of the substrate portion 1 of the wafer level lens array disposed above is placed on the upper surface of the substrate portion 1 of the wafer level lens array disposed below. , And joined through the spacer 12. In a state where the wafer level lens arrays are overlapped with each other, the position of the spacer 12 with respect to each substrate unit 1 is set to be the same in each substrate unit 1.

  Next, a semiconductor substrate W on which a plurality of solid-state imaging elements D are arranged is prepared. The alignment of the semiconductor substrate W with the substrate portions 1 of the plurality of wafer level lens arrays in a superposed state is performed. Thereafter, the substrate portion 1 positioned at the lowermost portion is bonded to the upper surface of the semiconductor substrate W via the spacer 12. At this time, the extension of the optical axis of each lens unit 10 provided on the substrate unit 1 intersects with the central part of the solid-state imaging device D.

  Then, as shown in FIG. 20B, after bonding the substrate unit 1 of the wafer level lens array and the semiconductor substrate W, the substrate unit 1 and the semiconductor substrate W are cut along a cutting line indicated by a dotted line in the drawing, Separated into a plurality of imaging units. At this time, the spacers 12 positioned on each cutting line are also cut simultaneously. The spacer 12 is divided with each cutting line as a boundary, and is attached to each imaging unit adjacent to each cutting line. In this way, an imaging unit including a plurality of lens units 10 is completed.

  In this way, a plurality of wafer level lens arrays are bonded to each other via the spacer 12, and then, the substrate portion 1 of the lowermost wafer level lens array and the semiconductor substrate W including the solid-state imaging device D are overlapped. The substrate portion 1 and the semiconductor substrate W are cut together in a dicing process. According to such a procedure, the separated lens modules are overlapped with each other, and further, the image pickup units are more efficiently compared with the case of manufacturing each image pickup unit by joining the lens modules and the sensor modules. Mass production is possible and productivity can be improved.

This specification discloses the following contents.
(1) A molding die for integrally molding a wafer level lens array comprising a substrate portion and a plurality of lens portions arranged on the substrate portion with a resin,
The mold comprises a pair of mold members that mold and cure the resin by sandwiching the resin and applying energy, and on the mold surface that contacts the resin of at least one mold member of the pair of mold members, A molding die for a wafer level lens array provided with an air vent hole for discharging air existing at the interface between the mold surface and the resin to the outside during molding.
(2) A mold for the wafer level lens array according to (1),
A mold for forming a wafer level lens array, wherein a plurality of recesses for transferring the lens portion having a convex lens surface are provided on the mold surface, and an air vent hole communicating with the outside of the mold member is provided in the recess. .
(3) A mold for molding a wafer level lens array according to (1) or (2),
A wafer level lens in which the lens portion includes a peripheral portion protruding in the same direction as the lens surface around the lens surface, and at least one air vent hole is provided in a concave portion of the mold surface corresponding to the peripheral portion. Array mold.
(4) A mold for molding a wafer level lens array according to (1),
A wafer in which a plurality of convex portions for transferring the lens portion having a concave lens surface is provided on the mold surface, and an air vent hole communicating with the outside of the mold member is provided in a concave portion between the convex portions. Mold for level lens array.
(5) A mold for molding a wafer level lens array according to (1) or (4),
A wafer level in which the lens portion includes a peripheral portion that protrudes around the lens surface in a direction opposite to the lens surface, and at least one air vent hole is provided in a concave portion of the mold surface corresponding to the peripheral portion. Lens array mold.
(6) A mold for a wafer level lens array according to any one of (2) to (5),
The air vent hole is a mold for forming a wafer level lens array provided at the deepest portion of the concave portion of the mold surface.
(7) The mold for a wafer level lens array according to any one of (2) to (6),
A mold for molding a wafer level lens array, wherein the air vent hole communicates with an air discharge path connected to a suction device that sucks air from the concave side toward the outside of the mold.
(8) A mold for a wafer level lens array according to any one of (1) to (7),
A mold for forming a wafer level lens array, wherein the air vent hole communicates with the opposite side of the mold surface.
(9) The mold for the wafer level lens array according to any one of (1) to (8),
A mold for molding a wafer level lens array, wherein the air vent holes are linearly provided inside the mold member.
(10) The mold for a wafer level lens array according to any one of (1) to (9),
A mold for forming a wafer level lens array, wherein the diameter of the air vent hole is 1/10 or less of the diameter of the recess.
(11) A mold for molding a wafer level lens array according to any one of (1) to (10),
A mold for forming a wafer level lens array, wherein the air vent hole has a circular cross section.
(12) A manufacturing method in which a wafer level lens array including a substrate portion and a plurality of lens portions arranged on the substrate portion is integrally molded with a resin,
The mold includes a pair of mold members that mold and cure the resin by sandwiching the resin and applying energy, and air is applied to the mold surface of at least one mold member of the pair of mold members. A method for manufacturing a wafer level lens array, wherein a punch hole is provided, and the resin is deformed while air is released from the air vent hole when the mold surface of the mold is pressed against the resin.
(13) The method for producing a wafer level lens array according to (12),
A method of manufacturing a wafer level lens array, wherein a recess is provided in the mold surface, and the air vent hole is provided in the recess.
(14) The method for producing a wafer level lens array according to (12) or (13),
A method of manufacturing a wafer level lens array, wherein air is sucked from a side communicating with the outside of the mold in the air vent hole.
(15) The method for producing a wafer level lens array according to any one of (12) to (14),
A method of manufacturing a wafer level lens array, wherein after the resin is cured, a protrusion left at a portion corresponding to the position of the air vent hole of the released lens portion is removed.
(16) The method for producing a wafer level lens array according to (15),
A method for manufacturing a wafer level lens array, in which the protrusions are removed by performing a cutting process on each lens part with a cutting surface parallel to the surface of the substrate part.
(17) The method for producing a wafer level lens array according to (15) or (16),
A method for manufacturing a wafer level lens array, wherein a light shielding process is performed on a portion of the lens portion from which the protrusion is removed.
(18) A wafer level lens array obtained by the method for producing a wafer level lens array according to any one of (12) to (17).
(19) A lens module obtained by dicing the substrate portion of the wafer level lens array according to (18) and dividing the substrate portion for each lens portion.
(20) A lens module obtained by dicing the substrate part of the wafer level lens array according to (18) and dividing the lens part for each lens part,
A lens module comprising a plurality of the substrate portions on which the lens portions are formed, wherein the plurality of substrate portions are overlapped with each other with the spacer interposed therebetween.
(21) An imaging unit comprising the lens module according to (19) or (20),
An image sensor;
A semiconductor substrate provided with the imaging device,
An imaging unit in which the substrate portion and the semiconductor substrate are integrally joined via the spacer.

  The manufacturing method of the wafer level lens array can be applied when manufacturing an imaging lens provided in an imaging unit of a digital camera, an endoscope apparatus, a portable electronic device or the like.

DESCRIPTION OF SYMBOLS 1 Substrate part 10 Lens part 12 Spacer 102,104 Mold member V1, V2 Air vent hole

Claims (21)

A molding die for integrally molding a wafer level lens array comprising a substrate portion and a plurality of lens portions arranged on the substrate portion with a resin,
The mold comprises a pair of mold members that mold and cure the resin by sandwiching the resin and applying energy, and on the mold surface that contacts the resin of at least one mold member of the pair of mold members, A molding die for a wafer level lens array provided with an air vent hole for discharging air existing at the interface between the mold surface and the resin to the outside during molding. A mold for forming a wafer level lens array according to claim 1,
A mold for forming a wafer level lens array, wherein a plurality of recesses for transferring the lens portion having a convex lens surface are provided on the mold surface, and an air vent hole communicating with the outside of the mold member is provided in the recess. . A mold for forming a wafer level lens array according to claim 1 or 2,
A wafer level lens in which the lens portion includes a peripheral portion protruding in the same direction as the lens surface around the lens surface, and at least one air vent hole is provided in a concave portion of the mold surface corresponding to the peripheral portion. Array mold. A mold for forming a wafer level lens array according to claim 1,
A wafer in which a plurality of convex portions for transferring the lens portion having a concave lens surface is provided on the mold surface, and an air vent hole communicating with the outside of the mold member is provided in a concave portion between the convex portions. Mold for level lens array. A mold for molding a wafer level lens array according to claim 1 or 4,
A wafer level in which the lens portion includes a peripheral portion that protrudes around the lens surface in a direction opposite to the lens surface, and at least one air vent hole is provided in a concave portion of the mold surface corresponding to the peripheral portion. Lens array mold. A mold for molding a wafer level lens array according to any one of claims 2 to 5,
The air vent hole is a mold for forming a wafer level lens array provided at the deepest portion of the concave portion of the mold surface. A mold for molding a wafer level lens array according to any one of claims 2 to 6,
A mold for molding a wafer level lens array, wherein the air vent hole communicates with an air discharge path connected to a suction device that sucks air from the concave side toward the outside of the mold. A mold for a wafer level lens array according to any one of claims 1 to 7,
A mold for forming a wafer level lens array, wherein the air vent hole communicates with the opposite side of the mold surface. A mold for forming a wafer level lens array according to any one of claims 1 to 8,
A mold for molding a wafer level lens array, wherein the air vent holes are linearly provided inside the mold member. A mold for forming a wafer level lens array according to any one of claims 1 to 9,
A mold for forming a wafer level lens array, wherein the diameter of the air vent hole is 1/10 or less of the diameter of the recess. A mold for a wafer level lens array according to any one of claims 1 to 10,
A mold for forming a wafer level lens array, wherein the air vent hole has a circular cross section. A manufacturing method in which a wafer level lens array comprising a substrate part and a plurality of lens parts arranged on the substrate part is integrally molded with a resin,
Using a mold composed of a pair of mold members that mold and cure the resin by sandwiching the resin and applying energy, air is vented to the mold surface of at least one mold member of the pair of mold members in contact with the resin A method of manufacturing a wafer level lens array, wherein a hole is provided, and the resin is deformed while air is released from the air vent hole when the mold surface of the mold is pressed against the resin. A method of manufacturing a wafer level lens array according to claim 12,
A method of manufacturing a wafer level lens array, wherein a recess is provided in the mold surface, and the air vent hole is provided in the recess. A method for producing a wafer level lens array according to claim 12 or 13,
A method of manufacturing a wafer level lens array, wherein air is sucked from a side communicating with the outside of the mold in the air vent hole. A method of manufacturing a wafer level lens array according to any one of claims 12 to 14,
A method of manufacturing a wafer level lens array, wherein after the resin is cured, a protrusion left at a portion corresponding to the position of the air vent hole of the released lens portion is removed. A method for producing a wafer level lens array according to claim 15,
A method for manufacturing a wafer level lens array, in which the protrusions are removed by performing a cutting process on each lens part with a cutting surface parallel to the surface of the substrate part. A method for producing a wafer level lens array according to claim 15 or 16,
A method for manufacturing a wafer level lens array, wherein a light shielding process is performed on a portion of the lens portion from which the protrusion is removed.   A wafer level lens array obtained by the method for manufacturing a wafer level lens array according to claim 12.   The lens module formed by dicing the said board | substrate part of the said wafer level lens array of Claim 18, and dividing | segmenting for every said lens part. A lens module obtained by dicing the substrate portion of the wafer level lens array according to claim 18 and dividing the substrate portion for each lens portion,
A lens module comprising a plurality of the substrate portions on which the lens portions are formed, wherein the plurality of substrate portions are overlapped with each other with the spacer interposed therebetween. An imaging unit comprising the lens module according to claim 19 or 20,
An image sensor;
A semiconductor substrate provided with the imaging device,
An imaging unit in which the substrate portion and the semiconductor substrate are integrally joined via the spacer.

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