JPH0143863Y2 - - Google Patents

Description

[Detailed Description of the Invention] (a) Field of Industrial Application The present invention relates to an etching apparatus that etches one side of a substrate to be etched.

(b) Conventional technology Conventionally, etching equipment has been used to perform single-sided etching of semiconductor substrates such as Si, SiO ₂ , GaSa, metals, plastic substrates, etc., especially Si semiconductor substrates (hereinafter simply referred to as substrates). Air bubbles adhere to the surface, causing uneven etching. The situation will be explained with respect to the etching apparatus shown in FIGS. 2 and 3.

Fig. 3a is a side view showing an example of a conventional etching device, Fig. 3b is a sectional view in the direction of the X-X' arrow shown in Fig. 3a, and Fig. 4 is a longitudinal section showing another example of the conventional etching device. It is a diagram.

In FIGS. 3a and 3b, a substrate 1 is placed on two rod-shaped jigs 3, one of which is held between a side plate 2 (not shown), and a substrate 1 is mounted on the side plate 2. A jig 4 is inserted into the notch and is mounted to fix the substrate 1. Furthermore,
In order to fix the jig 4, a fixing jig 5 having a trapezoidal cross section is fitted into the side plate 2. Then, the etching liquid 6 is jetted in one direction as shown by arrow A on the surface of the substrate 1. Note that this device uses a rotating body (not shown)
It is configured to be connected to and rotate as shown by arrow R.

Further, in FIG. 4, on the upper part of a rotating body 8 having a chuck 8a to which the substrate 1 is attached, the ejection opening of a nozzle 9 is arranged at a position equidistant from the plane of the substrate 1. Then, the etching liquid 6 is jetted from the spout of the nozzle 9 toward the substrate 1 in the vertical direction, that is, in the direction of arrow B. Further, the substrate 1 is rotated as shown by an arrow R by the rotating body 8 .

Thus, when etching the substrate 1, as shown in FIGS. 3a and 3b, the etching solution is jetted in the direction of arrow A using a pump (not shown) or the like while rotating the apparatus. This apparatus can provide a good finish when etching the entire surface of the substrate 1. Note that a SiO ₂ film is provided in the portions that are not etched.

(c) Problems to be solved by the invention However, in any of the etching processes, there were problems when performing single-sided etching.
The problems will be explained in detail below with reference to the drawings.

First, referring to FIG. 3, when selectively etching the substrate 1 by jetting the etching liquid 6 in the direction of arrow A (the situation is shown in FIG. 5), as the etching progresses, the etching becomes deeper. , the etching liquid 6 does not flow smoothly, and air bubbles adhere to the etching surface, making it difficult to remove the air bubbles. Therefore, the rotational speed of the rotating body may be increased to remove air bubbles, but a flow pattern of dirty and clean etching liquid is created in the etching solution, and the etching finish is not uniform in depth. Note that FIG. 5 is a cross-sectional view showing a part of the substrate 1 selectively etched, and a pattern of SiO ₂ film 10 is formed on the surface of the substrate 1, and a deep portion 1a surrounded by a broken line is etched. Processed.

Furthermore, the above-mentioned bubbles will be explained with reference to FIGS. 6 and 7.

Figures 6 a-1, b-1, and c-1 show the state in which air bubbles adhere to the etching surface during etching, and figure a-1 is the one produced by the etching apparatus of the present invention, which will be described later, and b-1. The figure shows the conventional figure 3, figure c-1 shows the conventional figure 4, and figure 6 a-2, b-2, c-2 shows the plurality of figures shown in figure 6. It is a cross-sectional view of one of the bubbles that adheres to the central part, and Figure a-2 is Figure A-1,
Figure b-2 corresponds to figure b-1, and figure c-2 corresponds to figure c-1. Further, FIG. 7 is an explanatory diagram for explaining problems caused by bubbles.

That is, FIG. 6b-1 shows that HF,
An etching liquid 6 such as HNO ₃ type is jetted. As the etching progresses, a plurality of small bubbles 12a, 12b with a diameter of 1 mm or less are attached to the dug-in portion 11a of the substrate 11.

Here, as shown in Figure b-2, since the etching liquid 6 is jetted in the direction of arrow A', the air bubbles 12a in the central part adhering to the dug part 11a are removed, but the air bubbles 12a attached to the dug part 11a are removed. The air bubbles 12b attached at the corners are difficult to remove because the etching liquid 6 flows poorly. For this purpose, as shown in Figure 7,
The substrate 11 directly under the bubble 12b is not dug, but the surrounding portion 11b is dug.

Next, in the etching apparatus shown in FIG. 4, the state is shown in FIGS. However, the bubbles 12b in the corner portions remain stationary due to the jets from the directions of arrows B and B' and are difficult to remove. Therefore, uneven etching as shown in FIG. 7 is likely to occur.

The present invention has been devised in view of the above-mentioned problems, and its purpose is to provide an etching device that prevents air bubbles from adhering to the etching surface and eliminates uneven etching.

(d) Means for solving the problem The means are: (1) an etching mechanism, namely (1)-1 a rotating body equipped with a chuck for attaching the substrate to be etched; (1)-2 a substrate to be etched; an inclined nozzle in which the etching liquid is jetted obliquely to the entire surface of the substrate to be etched; 1)-3 An etching mechanism consisting of a vibrating body that vibrates either the rotating body or the tilted nozzle, or both of them, and (2) a fixing base that fixes the etching mechanism. A technical measure has been taken in which the axial direction of the etching table is either perpendicular to the horizontal plane of the fixing table or inclined so as not to prevent the jetting of the etching liquid on the surface of the substrate to be etched.

Hereinafter, its operation will be explained in detail based on the drawings shown in the examples.

(E) Embodiment FIG. 1 is a longitudinal sectional view showing one embodiment of the etching apparatus according to the present invention, and FIG. 2 is a longitudinal sectional view showing another embodiment. are parts that have the same function.

In FIG. 1, the etching mechanism is a rotating body 8.
, an inclined nozzle 13, and a vibrating body (not shown). The rotating body 8 has a chuck 8 for attaching the substrate 1 shown in FIG. 4 as a substrate to be etched.
A is provided. Further, the ejection opening of the inclined nozzle 13 is at an equal distance l from the plane of the substrate 1, and the flow path of the jetting etching liquid 6 has an inclination angle θ ₁ of, for example, 45 degrees with respect to the axial direction of the rotating body 8 . It is partitioned by a plurality of rectifier plates 17 as shown in FIG. Therefore, the etching liquid 6 is jetted over the entire surface of the substrate 1 in the direction of arrow C. Further, the vibrating body has a structure such that the inclined nozzle 13, the rotating body 8 , or both can vibrate.

Furthermore, this etching mechanism is fixed to a fixed base 14 so that the inclination angle θ ₂ in the axial direction of the rotating body 8 is 90° with respect to the horizontal plane of the fixed base 14.

Furthermore, in FIG. 2, the components are almost the same as those shown in FIG . is inclined. That is, the inclination angle θ ₁ between the axial direction of the rotating body 16 and the flow path direction of the inclined nozzle 15, and the axial inclination angle θ ₃ of the rotating body 16 with respect to the horizontal plane of the fixed base 14.
and are almost equal angles of 45°. In addition,
The angle of inclination of the flow path in the inclined nozzle with respect to the axial direction of the rotating body is preferably 45 degrees, but is not limited to this. Furthermore, it is desirable that the angle of inclination in the axial direction with respect to the fixed base 14 has an upper limit of 90 degrees and a lower limit of approximately 45 degrees, but is not limited thereto. Further, in FIG. 2, the explanation is given for the position in the first quadrant of the coordinates, but the same can be said for the positions in the other quadrants.

Thus, in the etching apparatus shown in FIGS. 1 and 2, the inclined nozzle 13 or 1
When the etching liquid 6 is jetted from the hole 5, the etching progresses to form a dug portion 11a as shown in FIG. 6a-1. Then, as in the conventional etching apparatus, the air bubbles 12a at the center of the dug-in portion 11a are of course removed, and the air bubbles 12b adhering to the corners are also removed. That is, the sixth
As shown in Figure a-2, the etching liquid 6 is jetted in the direction of arrow C' onto the bubbles 12b at the corners. On the other hand, since the substrate 11 attached to the chuck 16a is rotated at a predetermined period by the rotating body 16 , the etching liquid 6 is also jetted in the direction of arrow C'' shown in FIG. 6a-1. Furthermore, although not shown in FIGS. 1 and 2, the vibration of the vibrating body further enhances the effect of removing the bubbles 12b at the corners.

(f) Effect of the invention As explained above, according to the invention, the substrate 11
Not only the air bubbles 12a in the center that adhere to the dug-in part 11a, but also the air bubbles 12b in the corner parts.
is also removed.

For example, when selectively etching a Si substrate using a SiO ₂ pattern, the accuracy of etching at 30 μm compared to other excavated areas is ±
It was within 1μm. Furthermore, in the case of no pattern, an accuracy of within ±0.5 μm was obtained with 30 μm etching.

Therefore, the etching apparatus according to the present invention is extremely useful in practice.

[Brief explanation of drawings]

FIG. 1 is a vertical cross-sectional view showing one embodiment of the present invention, FIG. 2 is a vertical cross-sectional view showing another embodiment of the present invention, and FIG. 3 a is a side view showing an example of a conventional etching apparatus. , FIG. 3b is the X- shown in FIG. 3a.
4 is a longitudinal sectional view showing another conventional example; FIG. 5 is a sectional view showing a part of selective etching of the substrate; FIGS. 6 a-1, b-1, c −
1 shows the state in which air bubbles were attached to the etching surface during etching process, and Fig. 6 a-2, b-2, c
-2 is a cross-sectional view of one of the plurality of bubbles shown in FIG. 6 adhering to the central portion, and FIG. 7 is a cross-sectional view showing uneven etching caused by the bubbles. DESCRIPTION OF SYMBOLS 1, 11...Substrate to be etched, 6...Etching liquid, 7...Chick, 8 , 16 ...Rotating body,
13, 15... Inclined nozzle, 14... Fixed stand, l
...Equidistance, θ _1~3 ...Inclination angle.

Claims (1)

[Scope of utility model registration request] In an etching device that etches one side of a substrate to be etched using a jet of etching liquid,
It is composed of an etching mechanism and a fixing base for fixing the etching mechanism, and the etching mechanism includes:
A rotary body having a chuck for attaching the substrate to be etched, and a spout through which the etching liquid is jetted are equidistant from the plane of the substrate to be etched, and a flow path through which the etching liquid is jetted is oriented with respect to the axial direction of the rotary body. an angled nozzle that is tilted in an oblique direction so that the etching liquid is jetted obliquely onto the entire surface of the substrate to be etched; and a vibrating body that vibrates either the rotating body or the angled nozzle, or the entirety of both. The axial direction of the rotating body of the etching mechanism is either perpendicular to the horizontal plane of the fixed base or inclined so as not to prevent the etching liquid from flowing on the surface of the substrate to be etched. Characteristic etching equipment.