JPH0616122B2 - Method of manufacturing chip-type multilayer interference filter - Google Patents

Description

The present invention relates to a method for producing a chip-type multilayer interference filter which is used, for example, by being attached to the light receiving surface of a pyro sensor used as a detection group of an infrared analyzer. Regarding

[Prior art]

Since the sensitivity of the pyrosensor is flat over a considerably wide wavelength range, a bandpass filter is required when using the pyrosensor as a detection group of an infrared analyzer to detect a specific wavelength. On the other hand, since the pyro sensor is very small, such as 2 to 3 mm square, the band pass filter also needs to be small accordingly.

By the way, the conventional multilayer interference filter as a bandpass filter has a bench cell diameter of 16 mm, 20 mm.
It is quite large, such as mm, and it was necessary to cut it into small chips in order to use it for the filter of the pyrosensor.

However, cutting the filter by any cutting means has the drawback that the multilayer film at the cutting edge is easily peeled off, and thus the yield is poor and mass production is not possible. Has the drawback that it adversely affects the special characteristics of the filter. In particular,
The smaller the chip filter, the higher the occupancy ratio of the peeled portion becomes, so that the above-mentioned drawback becomes more remarkable and becomes unusable.

[Object of the Invention]

The present invention has been made in view of the above matters, and an object thereof is to provide a method capable of manufacturing a chip-type multilayer interference filter filter having good performance with high yield.

[Structure of Invention]

In order to achieve the above object, in the present invention, a mask having a plurality of openings having a desired size and having a thickness sufficient to maintain the adhesion to the substrate in a high temperature state is provided. A method of manufacturing a chip-type multilayer interference filter in which high-refractive-index material particles and low-refractive-index material particles are alternately vacuum-deposited from a vapor deposition source on a substrate that is in close contact and is exposed through light opening of a mask in that state. In the above, as the mask, each of the refractive index substance particles flying in an oblique direction with respect to the normal line direction of the opening surface is further projected so as to thin the opening peripheral edge on the substrate side in the opening High refraction is achieved by using an etching process to integrally form a step on the exposed surface of the substrate facing the exit side through the wide entrance to reach the narrow exit side. Rate material particles and The refractive index material particles, not arrive to cut part of the substrate, and so that no shadows are not deposited on the opening edge of the mask on the exposed surface, so that laminated sequentially multilayered.

〔Example〕

FIG. 1 shows an example of a manufacturing process in a method for manufacturing a chip-type multilayer interference filter according to the present invention. In FIG. 1, 1 is a substrate made of, for example, sapphire, 2 is an opening 3 having a desired size. It is a mask with multiple openings. The size of the opening 3 may be determined according to the size of the filter required, and when the filter used for the pyrosensor is manufactured, the size may be 2 to 3 mm. Moreover, it is preferable that the number of the openings 3 is as large as possible. This is because the cost can be reduced by mass production.

The periphery of the opening 4 on the front surface side of the mask 2 is thinly formed by forming a step 4 as shown in FIGS. 2 and 3. The step 4 can be formed by, for example, an etching process. The reason for providing the step 4 in this way is as follows. That is, if the mask 2 is thick,
When the high-refractive-index substance particles and the low-refractive-index substance particles are alternately blown toward the substrate 1, when the flying directions of these respective refractive-index substance particles are oblique as shown in FIG. This is because a shaded portion A is generated at the edge of the area, and the vapor deposition substance does not reach this portion A. Therefore, it is preferable that the mask 2 be thin. However, if the mask 2 is too thin, the temperature of the substrate 1 reaches 200 ° C. or more during vacuum deposition, and the mask is bent by heat, so that the adhesion between the substrate 1 and the mask 2 is high. There is an inconvenience that it becomes worse.

Therefore, the mask 2 itself is thickened so as not to be bent by the temperature of the substrate 1, and the periphery of the opening is thinned by the step 4 so that the edge of the opening 3 is not shaded by the deposition substance. By forming the mask 2, both the inconvenience caused by the thick mask 2 and the inconvenience caused by the thin mask 2 are eliminated at once.

When manufacturing a chip-type multilayer interference filter,
As shown in FIG. 2A, the mask 2 is fixed in a state of being aligned with the substrate 1. The both 1 and 2 can be fixed by, for example, attaching a polyimide adhesive tape to several places on the peripheral portion. When the mask 2 is fixed to the substrate 1, in that state, as shown in FIGS.
, And attach it in place on the dome 6 of the vacuum deposition apparatus. Then, the high-refractive-index substance particles and the low-refractive-index substance particles are alternately skipped from the vapor deposition source 7 to perform vacuum vapor deposition.
In this case, since the mask 2 having the openings 3 is fixed to the substrate 1, the vapor deposition material adheres only to the substrate 1 exposed from the openings 3 of the mask 2. In addition, since the step 4 is formed around the opening 3 of the mask 2, there is no shadow around the opening 3 and vapor is completely deposited on the substrate 1 exposed from the opening 3. In this case, Ge and ZnS, for example, are used as the high refractive index substance and the low refractive index substance, respectively.

Then, the above-mentioned vacuum deposition is alternately performed on both surfaces of the substrate 1 a predetermined number of times. In this case, it goes without saying that the mask 2 is aligned with the substrate 1 so that the deposition material is deposited on the same position on both the front and back surfaces.

When the vacuum deposition on both surfaces of the substrate 1 is completed in this way, the substrate 1 is removed from the holder 5, and then the mask 2 is removed from the substrate 1 as shown in FIG. As shown in (e), the vapor deposition material 8 is formed on the substrate 1.
The substrate 1 is cut along the part 9 to be cut, which is not attached. By this cutting, it is possible to obtain a chip type multilayer interference filter as shown in FIG.

Further, since the cutting can be performed along the place where the vapor deposition substance 8 is not attached, the vapor deposition substance 8 is not peeled off.

Further, in this embodiment, when the mask 2 is thick, when the high refractive index substance particles and the low refractive index substance particles are alternately blown toward the substrate 1, the flying directions of these respective refractive index substance particles are diagonal. In that case, a shadowed portion A is formed on the edge of the opening 3 and the vapor deposition substance does not adhere to the portion A, so that the opening 2 has a thin peripheral edge. Therefore, when the mask 2 is removed from the substrate 1 after the vacuum deposition is completed,
On the substrate, the size corresponding to the opening 3 of the desired size,
A chip-type multi-layer interference filter is formed on which the vapor deposition material is thoroughly deposited.

As described above, in the present embodiment, the mask used for the oblique vapor deposition method should preferably be thin so as to eliminate a shadowed portion which is not vapor-deposited on the edge of the opening 3, but if it is thin, the mask formed by vacuum vapor deposition will be used. At this time, since the substrate temperature reaches 200 ° C or higher, the mask 2
Is bent by heat and the adhesion between the substrate 1 and the mask 2 is deteriorated, so that the edge of the opening 3 is formed thin so that the edge of the opening 3 is not shaded by the evaporation material. However, the inconvenience caused by the thick mask 2 and the mask 2
Both of them can solve the inconvenience caused by the thinness at once.

Then, in the above-described embodiment, the opening 3 of the mask 2 is used.
Since the mask 2 is subjected to the etching process in order to form the step 4 in the mask 2, the step 4 can be formed integrally with the mask 2, and the processing is easy.

〔The invention's effect〕

As described above, the present invention has the following effects.

a. A mask with multiple openings is fixed to the substrate to prevent the deposition material from adhering to the part to be cut of the substrate, and in that state, the high refractive index material particles and the low refractive index material particles are exposed on the substrate exposed from the openings of the mask. Since the refractive index substance particles are alternately vacuum-deposited, the problem that the vapor deposition substance peels off from the substrate does not occur even if the substrate is cut into small chips after vacuum vapor deposition, and therefore the yield can be improved. At the same time, a filter with good performance can be obtained.

b. For diagonal passage of high-refractive-index particles and low-refractive-index particles (oblique vapor deposition method), a mask with a step formed to thin the peripheral edge of the opening is used on the exit side of the opening, resulting in a wider area. Each of the refractive index substance particles that have passed through the opening entrance reaches the narrow opening, thereby eliminating a shadowed portion which is not vapor-deposited on the edge of the opening of the mask on the exposed surface of the opposed substrate, and is exposed. The vapor deposition material can be deposited over the entire surface.

That is, when the mask is thick, when the high refractive index substance particles and the low refractive index substance particles are alternately blown toward the substrate, when the flying direction of each of these refractive index substance particles is an oblique direction,
Since the shadow of the edge of the opening is formed and the vapor deposition material does not adhere to that portion, the peripheral edge of the opening of the mask is formed thin. Therefore, after completing the vacuum deposition,
By removing the mask from the substrate and cutting along the part to be cut without the deposition material attached, a size without a non-deposited shadow part corresponding to an opening of a desired size is formed on the cut substrate. It is possible to form a chip-type multi-layer interference filter having a vapor deposition material of a thickness.

． The mask used in the method of the present invention is provided with a step formed in each of the openings formed in the mask by subjecting the mask to an etching process. Therefore, a mask having such a characteristic structure is provided. The mask is easy to form, and the step is formed integrally with the mask, so that a mask that does not bend and has excellent adhesion to the substrate can be obtained. Therefore, a large amount of chip type multilayer interference filters having desired characteristics can be obtained at one time.

[Brief description of drawings]

1 to 3 show an embodiment of the present invention, FIG. 1 is a view showing a manufacturing process of a manufacturing method of a chip type multilayer interference filter, FIG. 2 is a front view of a mask used in the manufacturing method, FIG. 3 is a sectional view of the mask. FIG. 4 is a diagram for explaining an inconvenience that occurs when no step is provided around the hole of the mask. 1 ... Substrate, 2 ... Mask, 3 ... Open hole, 4 ... Step,
8 ... Evaporated substance, 9 ... Part to be cut.

Continuation of the front page (56) Reference JP-A-55-115004 (JP, A) JP-A-58-73127 (JP, A) JP-A-53-75858 (JP, A)

Claims (1)

[Claims] 1. A mask having a thickness sufficient to maintain the adhesiveness to the substrate in a high temperature state and having a plurality of apertures of a desired size adhered to the substrate, and the mask in that state In the method of manufacturing a chip-type multilayer interference filter in which high-refractive-index material particles and low-refractive-index material particles are alternately vacuum-deposited from a vapor deposition source on a substrate exposed through the openings of Each of the refractive index substance particles flying obliquely with respect to the normal line direction of the opening surface passes through a wider entrance so that the opening edge of the opening on the substrate side is thinned. , A high-refractive-index material particle and a low-refractive-index material particle are used by integrally forming a step that allows deposition material to adhere to the exposed surface on the substrate that is arranged facing the exit side by reaching the narrow exit side. Refractive index particles and A method for manufacturing a chip-type multilayer interference filter, characterized in that the multilayer structure is sequentially laminated so that it does not reach a predetermined cut portion and does not have a shadow that is not vapor-deposited on the edge of the opening of the mask on the exposed surface. .