JPS6198518A - Manufacture of mold - Google Patents

Abstract

PURPOSE:To enable a mold to have a gradient of up to 1 deg., by providing a step on a substrate that will determine the gradient, applying a fluidible substance thereon that will be required to determine the gradient, and heat-treating them. CONSTITUTION:A step layer 2 of SiO2 or the like having a thickness corresponding to the required gradient is formed in place on a substrate 1 of silicon or the like. A substance 3 that can be fluidized by heat treatment is applied on the substrate 1 including the step layer 2 in an amount so that the substance 3 has a thickness (z). When they are heat-treated in an oven having a temperature of 1,100 deg.C, the substance 3 is softened and the part thereof that is located on the step layer 2 flows downward, resulting in a gentle slope 5 on the substrate 1. Finally, a film 4 of a metal such as copper, gold, or rhodium is applied on the substance 3 for example by vacuum deposition so as to improve the releasability of a molded item from the thus produced mold.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a method for manufacturing a mold for producing an optical element, particularly a microlens by plastic stick molding.

[Conventional technology]

Various methods have been proposed for manufacturing molds used to manufacture microlenses made of plastic, one of which is machining, and the other is Semiconductor process or SJI 11-t-A
Book A - Among these, the former method is to make lines by marking the surface of the metal plate that will become the mold with a diamond needle or the like. In addition, as the first method of the latter, 5ho formed on a silicon substrate
There is a method of creating a curved surface by etching the Z film in a stepwise manner and then covering the stepped portion with a resin.A second method of the latter is a method using a taper etching method. This second
In the same method, a RhO2 film on a silicon substrate is used as the etching base material, and phosphosilicate glass (PSG), which is a material with a faster etching rate than RhO2, is deposited on top of the RhO2 film, and then etching is performed to form a taper. It's a method.

[Problem that the invention attempts to solve]

The conventional methods described above have various problems.

First, the machining method has the drawbacks that it takes time to prepare the grinding tool, and that machining irregularities, so-called feed pitch irregularities, occur during mold manufacturing.
There are many problems such as restrictions on processing for miniaturization.

The first method of the latter, in which the 5AO2 film is etched in a stepwise manner and then covered with a resin film (for example, Japanese Patent Application No. 18.698/1982), involves completely covering the corners of the steps with resin. Therefore, a resin with high viscosity is required. However, there is a problem in that resins with high viscosity are extremely difficult to handle.

The second latter method, the taper etching method, has the advantage of requiring only one etching process and a short process, but it is difficult to select the layer to be deposited on the etching base material (for example, 5=Q2). In this case, the conditions are that it must be able to be etched with the same etchant as the base material and that the etching speed must be faster than that of the base material. This not only greatly limits the materials that can be used as a layer to be deposited on the etching base material, but also poses problems such as the etching ratio being only about 10 times the base material at most.

i Also, when one side of the plastic that makes up the lens is taken as a horizontal plane, that is, a reference plane, the other side has an angle θ with respect to the reference plane [although it is inclined, in each of the conventional methods described above, There are five problems in that the inclination, that is, the angle 0, cannot be made less than 1 degree.

[Means for solving problems]

The present invention provides steps that determine the inclination of the substrate,
A flowable material is further modified by heat treatment in an amount necessary to determine the slope, and the material is made to flow by heat treatment to form the slope.

[Effect]

The present invention is an application of the conventional so-called "S70 technology", and therefore, the inclination can be freely determined by the step formed on the substrate. Furthermore, it is now possible to manufacture a molding mold with a small inclination angle, and it has become possible to manufacture a molding mold with a nod, that is, θ of 1° or less, which was previously impossible.

〔Example〕

Hereinafter, the method according to the present invention will be described with reference to a method for forming an inclined surface having an inclination of 0.86° as shown in FIG.

First, as shown in Fig. 3, a substrate (1
), the thickness 5 (5
A step layer (2) of 5=Oz, etc. having a wind of 3Qμ is formed. In this case, the width y of the step layer (2) can be selected to be 12μ.

Next, as shown in FIG. 4, the substrate (including the top of the step layer (2)
1) A substance (3) which can be flowed by heat treatment is deposited on the substrate to a thickness of 1 and 2. This heat-treated flowable material (
As for 3), phosphosilicate glass (PSG) can be used, and when PSG is used, the above-mentioned thickness 2 can be selected to be, for example, 20000X.

Next, a substrate (
When IJ is heat treated in a furnace at 1100°C, substance (3),
In this case, the PSG softens and a part of it flows out to the lower part of the step formed by the step layer (2), and as a result, a gently sloped surface (5) can be obtained as a whole as shown in Fig. 5. . This is the inclined surface having the desired angle θ.

Finally, as shown in Figure 1, a metal film such as copper, gold, or rhojucum is deposited on the substance (3) by vacuum evaporation, for example.
4) to improve the releasability between the mold and the molded product (glass lens).

By this method, as shown in Figure 2, the length of the non-flat part, that is, the sloped part, is 20 μm, and the difference in level is 0.3 μm, so the slope is 11 = 0.86. It becomes ゜.

Of course, by appropriately selecting the height or thickness X of the step layer (2) and the thickness 2 of the material (2) in the process shown in FIG. 4, the slope or angle θ can be arbitrarily selected. it is obvious. Further, a resin can also be used as the heat-treated flowable material (3).

[Effects of the Invention] The greatest effect of the present invention is that the slope of the slope, that is, θ, can be made less than or equal to 1. Moreover, the slope is
It can be freely changed by changing the height of the stepped layer (2) and the thickness of the material (3).

Furthermore, it has the feature of being much simpler than the prior art.

[Brief explanation of the drawing]

Fig. 1 is a cross-sectional view of a mold manufactured by the method of the present invention, Fig. 2 is an explanatory diagram showing an example of the dimensions of the mold, and Figs. It is a process diagram showing one example. (1) is a substrate, (2) is a stepped layer, (3) is a heat-treated flowable material, and (4) is a metal film. Figure 2 Figure 5 Date of 1985 Mr. Uga Michibu, Commissioner of the Patent Office, Patent Application No. 219954 3, Relationship with the case of the person making the amendment Patent Applicant's Address: Tokyo Parts-Yo-ku Kita Item name 6-7 @35 name (2
18) Sony Corporation Representative Director Norio Ohga 4, Agent Address: 1-8-1 Nishi-Shinjuku, Shinjuku-ku, Tokyo 03-
343-5821ft5 (Shinjuku Building) 6, Number of inventions increased by amendment 7, Subject of amendment Column for detailed explanation of the invention in the specification, column for brief explanation of drawings, and drawings. In the specification, page 5, line 1 r30#mJ is ro, 3. umJ
I am corrected. @ Same, bottom line of page 5 to line 1 of page 6 “The deposit is applied to the mold...
·Improve. '' should be corrected as follows. When forming a plastic layer, electroplating is performed using this metal film (4) as an electrode, and when this electroplated layer has a certain thickness, it is removed from the metal film (4). It is peeled off and used as a molding mold.The reason why the mold is obtained by plating is that the mold used for plastic molding is a consumable item.
The component shown in the figure is used as a master plate, and a plurality of molds are made from this base plate. Incidentally, for the step of peeling off the electroplated layer described above from the metal film (4), a generally known technique can be used as is. '', page 6, line 10, ``It can also be done,'' followed by a new line and the following addition. ``As mentioned above, using the component shown in Figure 1 as an original plate, electroplating is further formed on the metal film (4) until it reaches a certain thickness, and then this electroplating layer is applied. metal l
It is also possible to peel off the metal 11 (41) and use it as a mold.
When peeling off the electroplated layer from 1 (41), there is a risk that the base material (11) made of silicon or the like may be damaged. To avoid this, as shown in FIG. ) is provided, and the original plate shown in Fig. 1 is placed on this surface (6) via an adhesive (8), placed in an open space, etc., heated, and the adhesive (8) is applied. It is preferable to fix the above-mentioned original plate on the pedestal (7) by curing it. This increases the thickness of the entire original plate, reinforces the substrate (1), and forms the electroplated metal film (4) as described above.
It is possible to avoid damage to this when peeling off the strands. J (4) Same, page 7, line 2, “It is a process drawing.”
FIG. 6 is a sectional view showing the mold shown in FIG. 1 in a further reinforced state. ” he corrected. (Replenish as shown in Figure 6 of page 51vlJ.

Claims (1)

[Claims] a step of forming a stepped layer on a substrate; a step of forming a material that can flow by heat treatment on the substrate and the step layer; A method for manufacturing a molding die, comprising the step of forming a curved surface on the top.