JPH0630352B2 - Patterned layer forming method - Google Patents

Description

TECHNICAL FIELD The present invention relates to a patterned layer forming method for forming a patterned layer on a substrate, and particularly to a finely patterned electrode layer, wiring layer, and insulating layer on the substrate. It is suitable for application in the case of manufacturing a semiconductor device having a structure in which a patterned layer made of, for example, is formed.

2. Description of the Related Art As a patterned layer forming method for forming a patterned layer on a substrate, the method described below with reference to FIG. 3 has been conventionally proposed.

That is, the substrate 1 is prepared in advance (FIG. 3A), and the photoresist layer 2 is formed on the substrate 1 by coating (FIG. 3B).

Next, the photoresist layer 2 is exposed to light using a photomask 3 having a desired pattern to obtain a photoresist layer 2'exposed to a pattern corresponding to the pattern of the photomask 3 from the photoresist layer 2 (first. (Fig. 3 C).

In this case, the exposed area of the photoresist layer 2'is slightly smaller than the non-hatched light passage area of the photomask 3 as shown by the hatching due to the lateral spread of light. , Has a large effective area around.

Then, a patterned photoresist layer 2 ″ having a pattern corresponding to the pattern of the photomask 3 is formed from the photoresist layer 2 ′ by etching the photoresist layer 2 ′ (FIG. 3D).

Next, the patterned photoresist layer 2 ″ is formed on the substrate 1.
The deposition process of the material of the target patterned layer using the mask as a mask has a pattern on the substrate 1 that is inverted with respect to the pattern of the patterned photoresist layer 2 ″ and that of the target patterned layer. Patterned layer 4 of material
Is formed as an intended patterned layer in a thickness smaller than that of the patterned photoresist layer 2 ″ (FIG. 3E).

In this case, on the patterned photoresist layer 2 ″, simultaneously with the patterned layer 4, the patterned layer 5 made of the same material as the patterned layer 4 is formed in the same pattern as the patterned photoresist layer 2 ″.

Next, the patterned photoresist layer 2 ″ is removed by a process of removing the patterned photoresist layer 2 ″ from the substrate 1.
The patterned photoresist layer 2 ″ and the patterned layer 5 formed on the patterned photoresist layer 2 ″ are removed from the substrate 1, so that the patterned layer 4 is formed on the substrate 1. (FIG. 3F).

The above is one example of the conventionally proposed patterned layer forming method.

Further, conventionally, a patterned layer forming method described below with reference to FIG. 4 has also been proposed.

That is, a substrate 1 similar to that shown in FIG. 3 is prepared in advance (FIG. 4A), and a photoresist layer 2 similar to that shown in FIG. 3 is formed on the substrate 1 by coating (fourth embodiment). (Figure B).

Next, by chemical treatment of the photoresist layer 2,
The region on the surface side of the photoresist layer 2 is converted into a photoresist layer 22 having a lower photosensitivity than the original photosensitivity, so that the photoresist layer 21 is formed from the region other than the photoresist layer 22. When,
A laminated body 23 including the photoresist layer 22 is formed (FIG. 4C).

Next, by performing exposure processing on the stacked body 23 using the photomask 3 having the same required pattern as in the case of FIG. 3, the photoresist exposed from the stacked body 23 to a pattern corresponding to the pattern of the photomask 3 is exposed. Photoresist layer 21 'by layer 21 and photoresist layer 22' exposed to a pattern corresponding to the pattern of photomask 3
A laminated body 23 'having a structure in which and are laminated is obtained (FIG. 4D).

In this case, the exposed region of the photoresist layer 22 'of the stacked body 23' is wider than the light-passing region of the photomask 3 which is not shaded as shown by the hatching because of lateral spread of light. , But has a slightly larger effective area. Further, since the photoresist layer 21 has a higher sensitivity than the photoresist layer 22 in the exposed region of the photoresist layer 21 ′, because of lateral spread of light, the photoresist layer 21 ′ is exposed as shown by the diagonal lines. Layer 22 '
The exposed area is slightly larger than that of the exposed area of the.

Next, by an etching process on the laminated body 23 ',
From the laminate 23 ', a patterned photoresist layer 2 "with a photoresist layer 21' having a pattern corresponding to the pattern of the photomask 3 and a photoresist layer 22 '.
To form a patterned laminate 23 ″ having a structure in which the photoresist layer 22 ″ according to the above is laminated (FIG. 4D).

In this case, since the exposed area of the photoresist layer 21 'of the laminate 23' has an effective area which is slightly larger than the exposed area of the photoresist layer 22 ', the patterned photoresist layer is formed. 21 "is formed as having a side surface slightly inside the side surface of the patterned photoresist layer 22".

Next, the photoresist layer 22 ″ of the patterned laminate 23 ″ is formed on the substrate 1 by depositing the material of the target patterned layer on the substrate 1 using the patterned laminate 23 ″ as a mask. Patterning layer 4 having a pattern that is the inverse of the pattern of FIG. 1 and made of the material of the target patterning layer, is formed to a target thickness that is thinner than the patterning photoresist layer 21 ″. It is formed as a layer (Fig. 4E).

In this case, the patterned layer 4 is such that the side surface of the patterned photoresist layer 21 ″ is the patterned photoresist layer 2 ″.
Since the side surface is slightly inward of the side surface of 2 ″, there is a slight distance between the side surface of the patterned layer 4 and the side surface of the patterned photoresist layer 21 ″.
Further, on the patterned photoresist layer 22 ″, simultaneously with the patterned layer 4, the patterned layer 5 made of the same material as the patterned layer 4 is formed in the same pattern as the patterned photoresist layer 22 ″.

Next, the patterned laminate 23 ″ is removed from the substrate 1 by an ablation process for the patterned laminate 23 ″,
Therefore, the patterned laminated body 23 ″ and the patterned layer 5 formed on the patterned laminated body 23 ″ are removed from the substrate 1, and the patterned layer 4 is formed on the substrate 1. (Fig. 4F).

The above is another example of the conventionally proposed patterned layer forming method.

Further, conventionally, a patterned layer forming method described below with reference to FIG. 5 has also been proposed.

That is, a substrate 1 similar to that shown in FIG. 3 is prepared in advance (FIG. 5A), and a photoresist layer 2 similar to that shown in FIG. 3 and a non-photosensitive material made of an inorganic material are provided on the substrate 1. Layer 31
And a photoresist layer 32 of the same material as the photoresist layer 2 are formed in that order to form a laminate 33 of the photoresist layer 2, the non-photosensitive layer 31, and the photoresist layer 32 ( FIG. 5B).

Next, by performing an exposure process on the laminated body 33 using the photomask 3 having a desired pattern, the photoresist layer 2 is exposed from the laminated body 33 in a pattern corresponding to the pattern of the photomask 3. 2 ', the non-photosensitive layer 31, and the photoresist layer 3 exposed in a pattern corresponding to the pattern of the photomask 3.
A laminate 33 'in which the photoresist layer 32' according to No. 2 and the photoresist layer 32 'are laminated in that order is obtained (FIG. 5C).

In this case, the exposed areas of the photoresist layers 2 ′ and 32 ′ are smaller than the shaded light passage areas of the photomask 3 as shown by the hatching due to the lateral spread of light. However, they have an effective area equal to each other and larger than each other.

Next, a patterned photoresist layer 32 ″ having a pattern corresponding to the pattern of the photomask 3 is formed from the photoresist layer 32 ′ by etching the photoresist layer 32 ′ of the laminated body 33 ′, and thus the laminated layer is formed. From the body 33 ', a laminate 33 "is formed in which the photoresist layer 2', the non-photosensitive layer 31, and the patterned photoresist layer 32" are laminated in that order (5D).

Next, the patterned photoresist layer 32 ″ with respect to the non-photosensitive layer 31 ′ and the photoresist layer 2 ′ of the laminate 33 ″.
By dry etching process using
From the non-photosensitive layer 31 to the patterned photoresist layer 3
A patterned non-photosensitive layer 31 'having a pattern corresponding to the 2 "pattern is formed, and the patterned photoresist layer 32' is similarly formed from the photoresist layer 2 '.
Forming a patterned photoresist layer 2 ″ having a pattern corresponding to the pattern of
A laminated body 33 '"is formed by laminating the patterned photoresist layer 2", the patterned non-photosensitive layer 31', and the patterned photoresist layer 32 "in that order (Fig. 5E).

In this case, since the patterned photoresist layer 32 ″ and the photoresist layer 2 ′ are also etched in the lateral direction, the patterned photoresist layers 32 ″ and 2 ″ are
It is formed to have a side surface slightly inside the side surface of the patterned non-photosensitive layer 31 '.

Then, the patterned laminate 33 ′ ″ is patterned on the substrate 1 by the deposition process of the material of the target patterned layer using the patterned laminate 33 ′ ″ as a mask. The patterned layer 4 having a pattern inverted with respect to the pattern of the photosensitive layer 31 'is formed as a target patterned layer in a thickness smaller than that of the patterned photoresist layer 2 "(fifth). (Figure E).

In this case, the patterned layer 4 has a side surface slightly inside the side surface of the patterned photoresist layer 2 ″ than a side surface of the patterned non-photosensitive layer 31 ′. There is a slight distance between the side surface and the side surface of the patterned photoresist layer 2 '. Also, the patterned layer is formed on the patterned non-photosensitive layer 31' and the patterned photoresist layer 32 ". 4 at the same time as patterned layer 4
Patterned layers 5 and 5'of the same material are formed.

Next, the patterned photoresist layers 2 ″ and 32 ″ are removed from the substrate 1 by a process of removing the patterned photoresist 33 ″ ″ from the patterned photoresist layer 2 ″. , Patterned laminate 33 ′ ″
Are removed together with the patterned layers 5 and 5'to obtain a structure in which the patterned layer 4 is formed on the substrate 1 (FIG. 5F).

The above is still another example of the method for forming a patterned layer that has been conventionally proposed.

Further, conventionally, a patterned layer forming method described below with reference to FIG. 6 has also been proposed.

That is, a substrate 1 similar to the case of FIG. 3 is prepared in advance (FIG. 6A), and the same photoresist layer 2 as in the case of FIG. A laminate 42 is formed by coating, in which a photoresist layer 41 made of a material having a slower etching rate than the photoresist layer 2 for the etchant used is laminated in that order (FIG. 6B).

Next, by performing an exposure process on the stacked body 42 using the photomask 3 having a desired pattern, the photoresist layer 2 is exposed from the stacked body 42 in a pattern corresponding to the pattern of the photomask 3. ′
And a photoresist layer 41 'formed of a photoresist layer 41 exposed in a pattern corresponding to the pattern of the photomask 3 are laminated in this order on the laminated body 42'.
Is obtained (FIG. 6C).

Next, by performing an etching process on the laminated body 42 ',
From the laminated body 42 ', a patterned photoresist layer 2'by a photoresist layer 2'having a pattern corresponding to the pattern of the photomask 3 and a patterned photoresist layer 41' by a photoresist layer 41 'having a similar pattern. Form a patterned laminate 42 ″ in which are laminated in that order (FIG. 6D).

In this case, in the laminated body 42 ″, since the photoresist layer 2 ′ has an etching rate higher than that of the photoresist layer 41 ′, the patterned photoresist layer 2 ″ has a higher etching rate than the side surface of the patterned photoresist layer 41 ″. It is formed as having an inner surface slightly inside.

Next, a patterned photoresist layer of the patterned laminate 42 ″ is formed on the substrate 1 by depositing the material of the target patterned layer using the patterned laminate 42 ″ as a mask on the substrate 1. The patterned layer 4 having a pattern that is the inverse of the 41 "pattern is formed as the target patterned layer with a smaller thickness than the patterned photoresist layer 2" (FIG. 6E). .

In this case, the patterned layer 4 is such that the side surface of the patterned photoresist layer 2'is the patterned photoresist layer 41 '.
Since it has a side surface slightly inside the side surface of
There is a slight distance between the side surface of the patterned layer 4 and the side surface of the patterned photoresist layer 2 ″.
On the patterned photoresist layer 41 ″, simultaneously with the patterned layer 4, the patterned layer 5 made of the same material as the patterned layer 4 is formed in the same pattern as the patterned photoresist layer 41 ″.

Next, the patterned laminate 42 ″ is removed from the substrate 1 by an ablation process for the patterned laminate 42 ″,
Therefore, the patterned laminate 42 ″ and the patterned layer 5 formed thereon are removed from the substrate 1 to obtain a structure in which the patterned layer 4 is formed on the substrate 1 (sixth). (Figure F).

The above is another example of the conventionally proposed patterned layer forming method.

Further, conventionally, a patterned layer forming method described below with reference to FIG. 7 has also been proposed.

That is, a substrate 1 similar to the case of FIG. 3 is prepared in advance (FIG. 7A), and the same photoresist layer 2 as in the case of FIG. A laminate 52 is formed by coating, in which a photoresist layer 51 made of a material having an etching rate higher than that of the photoresist layer used for the etchant used is laminated in that order (FIG. 7B).

Next, by performing an exposure process on the stacked body 52 using the photomask 3 having a desired pattern, the photoresist layer 2 is exposed from the stacked body 52 to a pattern corresponding to the pattern of the photomask 3. ′
And a photoresist layer 51 'formed of a photoresist layer 51 exposed in a pattern corresponding to the pattern of the photomask 3 are laminated in that order.
Is obtained (FIG. 7C).

Next, by performing an etching process on the laminated body 52 ',
From the laminated body 52 ', a patterned photoresist layer 2'by a photoresist layer 2'having a pattern corresponding to the pattern of the photomask 3 and a patterned photoresist layer 51' by a photoresist layer 51 'having a similar pattern. A laminated body 52 ″ in which and are laminated in that order
Are formed (FIG. 7D).

In this case, in the laminated body 52 ″, since the photoresist layer 2 ′ has a slower etching rate than the photoresist layer 51 ′, the patterned photoresist layer 51 ″ is larger than the side surface of the patterned photoresist layer 2 ″. It is formed as having an inner surface slightly inside.

Next, by the deposition process of the material of the target patterned layer using the patterned laminated body 52 ″ as a mask on the substrate 1, although it is thinner than the patterned laminated body 52 ″ on the substrate 1, Thicker than the patterned photoresist layer 2 ″,
Is formed to have a thickness (Fig. 7E).

In this case, the patterned layer 4 is formed with a patterned layer portion 4a having a pattern that is inverted with respect to the pattern of the patterned photoresist layer 2 ″ and an area that is slightly larger than the patterned layer portion 4a. The semiconductor layer portion 4b has a pattern that is the reverse of the pattern of the patterned photoresist layer 52 ″, and has a T-shaped cross section. On the patterned photoresist layer 52 ″, simultaneously with the patterned layer 4, a patterned layer 5 made of the same material as the patterned layer 4 is formed in the same pattern as the patterned photoresist layer 52 ″.

Next, the patterned laminate 52 ″ is removed from the substrate 1 by the ablation treatment on the patterned laminate 52 ″,
Therefore, the patterned laminated body 52 ″ and the patterned layer 5 formed thereon are removed from the substrate 1 to obtain a structure in which the patterned layer 4 is formed on the substrate 1.

The above is still another example of the method for forming a patterned layer that has been conventionally proposed.

Problems to be Solved by the Invention In the case of the conventional patterned layer forming method described above with reference to FIG. 3, a photoresist is used as a layer to be formed on the substrate 1 in the step (FIG. 3D) before the exposure process. Since only one layer 2 is required, the desired patterned layer 4 can be easily formed.

However, in the step (FIG. 3D) of forming the patterned photoresist layer 2 ″ from the photoresist layer 2 ′ by an etching process, the photoresist layer 2 ′ is formed.
Since it is difficult to etch the photoresist layer 2 ′ to a width less than the thickness thereof, the patterned layer 4 is finely patterned unless the photoresist layer 2 ′ and therefore the photoresist layer 2 is formed to a thin thickness. It had a defect that it could not be formed as a product.

For this reason, when the photoresist layer 2 is formed to have a small thickness, the patterned layer 4 is formed on the patterned photoresist layer 2 ″ in the step of forming the patterned layer 4 (FIG. 3E). When the patterned photoresist layer 2 ″ is finally removed to remove the patterned photoresist layer 2 ″ (third pattern), the patterned photoresist layer 2 ″ may be formed in contact with the patterned layer 5 to be formed. Figure F) had the drawback that the patterned layer 4 was not obtained as having a well-defined pattern.

Further, in the step of forming the patterned layer 4 on the substrate 1 and then removing the patterned photoresist layer 2 ″ from the substrate 1 (FIG. 3F), the patterned photoresist layer 2 ″ is patterned. Since it is connected between the chemical layer 4 and the side surface,
It has the disadvantage that it takes time to evaporate the patterned photoresist layer 2 ″ and thus to form the patterned layer 4.

Further, in the case of the conventional patterned layer forming method described above with reference to FIG. 4, a step of forming the patterned layer 4 on the substrate 1 and then removing the patterned photoresist layer 2 ″ (FIG. 4G). In FIG. 3, since the patterned layer 4 is not connected to the patterned photoresist layer 2 ″ between the side surfaces, the patterned photoresist layer 2 ″ is compared with the case of the conventional patterned layer forming method described above with reference to FIG. However, the patterned layer 4 can be easily removed in a short time, and thus the patterned layer 4 can be easily formed in a shorter time than in the case of FIG.

However, due to the etching process, the laminated body 23 '
In the step of forming the patterned laminate 23 ″ from FIG. 4 (FIG. 4D), it is difficult to etch the laminate 23 ′ to a width less than its thickness, so that the laminate 23 ′ and thus the photoresist layer 2 Unless formed to a thin thickness
It has the drawback that the patterned layer 4 cannot be formed as being finely patterned.

Further, for this reason, when the photoresist layer 2 is formed to have a small thickness, in the step of forming the patterned layer 4, the patterned layer 4 is formed on the stacked body 23 ″. May be formed in connection with
Therefore, when the patterned laminate 23 ″ is removed from the substrate 1 to finally obtain the patterned layer 4 (FIG. 4G), the patterned layer 4 has a pattern with a clear contour. It had the drawback that it could not be obtained.

Further, after the photoresist layer 2 is formed on the substrate 1, the photoresist layer 2 is removed from the photoresist layer 2 by a chemical treatment on the photoresist layer 2 and the photoresist layer 22 having a lower photosensitivity. Step of forming a laminated body 23 in which and are laminated (FIG. 4C)
And it is difficult to form the photoresist layer 22 of the stacked body 23 with good reproducibility,
It has a drawback that it is difficult to form the patterned layer 4 in a desired pattern with good reproducibility.

Further, in the case of the conventional patterned layer forming method described above with reference to FIG. 5, in the process of forming the patterned layer 4 on the substrate 1 and then removing the patterned laminate 33 ′ ″ from the substrate 1 (see 5G), the patterned photoresist layer 2 ″ is not connected to the patterned layer 4, so that the patterned photoresist layer 2 ″ can be easily removed in a shorter time than in the case of FIG. , Thus the patterned laminate 33 ′ ″
Can be easily removed from the substrate 1 in a short time, and thus the patterned layer 4 can be easily formed in a short time.

Further, in the step of forming the patterned layer 4 (FIG. 5F), the patterned layer 4 includes the patterned photoresist layer 2 ″, the patterned non-photosensitive layer 31 ′, and the patterned photoresist layer 32. Using the patterned laminated body 33 ′ ″ having a structure in which “and” are laminated as a mask, the substrate 1
On top, the patterned laminate 33 '"is formed to a thickness less than the patterned photoresist layer 2", while the patterned non-photosensitive layer 31' of the patterned laminate 33 '"is thicker. The patterned layer 4 does not have to be formed in contact with the patterned layer 5 formed on the patterned laminated body 33 ″, and therefore the patterned laminated body 33 ′ ″ is formed. Are removed from the substrate 1 to form the patterned layer 4
Finally, the patterned layer 4 is obtained.
Are obtained as having a clear outline pattern.

However, the photoresist layer 32 'of the laminate 33'
Etching treatment for the non-photosensitive layer 3 of the laminate 33
1 and the photoresist layer 2 ′ need to be etched twice, and since the contents of the etching treatments are different from each other, the patterned layer 4 cannot be easily formed. Had.

Further, in the case of the conventional patterned layer forming method described above with reference to FIG. 6, in the step of removing the patterned laminated body 42 ″ from the substrate 1 after forming the patterned layer 4 on the substrate 1 (6th step). FIG. F), the patterned photoresist layer 2 ″ of the patterned laminate 42 ″ is not in contact with the patterned layer 4, so that the patterned laminate 42 ″ can be easily removed in a short time. The patterned layer 4 can be easily formed in a short time.

In the step of forming the patterned layer 4 (FIG. 6E), the patterned layer 4 has a structure in which the patterned photoresist layer 2 ″ and the patterned photoresist layer 41 ″ are laminated. The patterned laminate 42 ″ is used as a mask to form a thin film on the substrate 1 as compared with the patterned photoresist layer 2 ″ of the patterned laminate 42 ″, while the patterned laminate 33 ″ is patterned. Since the photoresist layer 41 'can be formed to have a large thickness,
There is no risk that the patterned layer 4 will be formed contiguously with the patterned layer 5 formed on the patterned laminate 42 ″, so that the patterned laminate 42 ″ is removed from the substrate 1. Thus, when the patterned layer 4 is finally obtained (FIG. 6F), the patterned layer 4 is obtained as a pattern having a clear contour.

However, in the step (FIG. 6B) before performing the exposure process, two layers of the photoresist layer 2 and the photoresist layer 41 are required as the layers formed on the substrate 1, and these photoresist layers are also required. 2 and the photoresist layer 41 has a limitation that the etching rates of etchants used in the etching process must be different from each other, and thus the patterned layer 4 can be formed at low cost. It had the drawback that it could not be done.

Further, in the case of the conventional patterned layer forming method described above with reference to FIG. 7, in the step of forming the patterned layer 4 (FIG. 7E), the patterned layer 4 is the patterned photoresist layer 2 ″, The patterned laminate 52 ″ having a structure in which the patterned photoresist layer 51 ″ is laminated is used as a mask, but is thinner than the patterned photoresist layer 2 ″ of the patterned laminate 42 ″ on the substrate 1. Since the patterned photoresist layer 51 ″ of the patterned laminate 52 ″ can be formed to be thicker than the patterned photoresist layer 2 ″, the patterned layer 4 can be formed to be thicker than the patterned photoresist layer 2 ″. There is no possibility of being formed in contact with the patterned layer 5 formed on the patterned laminated body 42 ″, and thus the patterned laminated body 52 ″ is removed from the substrate 1,
When the patterned layer 4 is finally obtained (Fig. 6F), the patterned layer 4 is obtained as having a well-defined pattern ".

Further, since the patterned layer 4 is formed in a T-shape in cross section, when applied to the case of forming a gate electrode layer of a Schottky junction field effect transistor, for example, the gate electrode layer has a short gate length. However, it can be formed with a low gate resistance, and is therefore suitable for application when forming a gate electrode layer of a Schottky junction field effect transistor.

However, in the step (FIG. 7B) before performing the exposure process, two layers of the photoresist layer 2 and the photoresist layer 42 are required as the layers formed on the substrate 1, and these photoresist layers are also required. 2 and the photoresist layer 42 has a restriction that the etching rates of the etchants used in the etching process should be different from each other, so that the patterned layer 4 can be formed at low cost. It had the drawback that it could not be done.

In addition, a step of forming the patterned layer 4 on the substrate 1 (seventh step).
After FIG. E), in the step of removing the patterned laminate 52 ″ by evaporation (FIG. 7F), since the patterned layer 4 is connected to the patterned laminate 52 ″ between the side surfaces, the patterned laminate is formed. It has the drawback that it takes a long time to evaporate away the body 52 ″, and thus to form the patterned layer 4.

By the means for solving the problem, the present invention proposes a new patterned layer forming method which does not have the above-mentioned drawbacks.

The patterned layer forming method according to the present invention takes the following sequential steps to form a desired patterned layer.

That is, first, a step of forming a first laminated body in which a first photoresist layer, a light passage limiting layer, and a second photoresist layer are laminated in that order on a substrate is taken.

Next, the first photoresist layer is exposed from the first laminate to a pattern corresponding to the pattern of the photomask by an exposure process using a photomask having a desired pattern for the first laminate. A third photoresist layer according to the above, the light passage limiting layer, and the second exposed to a pattern corresponding to the pattern of the photomask.
The step of obtaining a second laminate in which the fourth photoresist layer of the photoresist layer of 1) and the fourth photoresist layer are laminated in that order is adopted.

Next, by etching the fourth photoresist layer of the second laminate, a first patterned photoresist layer having a pattern corresponding to the pattern of the photomask is formed from the fourth photoresist layer. Take the step of forming.

Then, the light-passage limiting layer of the second laminate is subjected to an etching treatment using the first patterned photoresist layer as a mask to remove the same light from the light-passage limiting layer as the first patterned photoresist layer. The step of forming a patterned light passage restriction layer having a pattern is taken.

Then, a second patterned photoresist layer having a pattern corresponding to the pattern of the photomask is removed from the third photoresist layer by etching the third photoresist layer of the second laminate. And thus forming a patterned laminate in which the second patterned photoresist layer, the patterned light passage restriction layer, and the first patterned photoresist layer are laminated in that order. Take steps.

Next, a step of forming a patterned layer made of the above material on the substrate is performed by depositing the material of the desired patterned layer on the substrate using the patterned laminate as a mask.

Next, a step of removing the patterned laminate from the substrate is carried out by an ablation treatment on the patterned laminate, whereby a desired patterned layer of the patterned layer is obtained on the substrate.

Example 1 Next, a first example of the patterned layer forming method according to the present invention will be described with reference to FIG.

The first embodiment of the method for forming a patterned layer according to the present invention takes the following sequential steps to form a desired method for forming a patterned layer.

That is, the same substrate 1 as in the case of FIG. 3 is prepared in advance (FIG. 1A).

Then, on the substrate 1, a photoresist layer 2 similar to the case of FIG. 3, a light passage limiting layer 61, and a photoresist layer 62 made of the same material as the photoresist layer 2 are laminated in that order. Forming a laminated body 63 (FIG. 1B).

In this case, the light passage restriction layer 61 allows light used in the subsequent exposure processing to pass therethrough, but has a transmittance of less than “1” for the light, or similarly, used in the subsequent exposure processing. Allows light to pass through, but changes in the direction of low or high transmittance for that light when exposed to that light,
For example, it is a layer made of a synthetic resin polymer into which a dye exhibiting photochronism is introduced.

Next, a third pattern having a desired pattern for the stack 63 is formed.
By the exposure process using the same photomask 3 as described above in the figure, the laminated body 63 exposes the photoresist layer 2'by the photoresist layer 2 exposed in a pattern corresponding to the pattern of the photomask 3, and the light passage restriction. A layered body 63 'is obtained in which a layer 61 and a photoresist layer 62' by a photoresist layer 62 exposed in a pattern corresponding to the pattern of the photomask 3 are laminated in that order (first).
(Figure C).

In this case, the exposed region of the photoresist layer 62 'of the laminated body 63' is wider than the light-passing region of the photomask 3 which is not shaded as shown by the hatching because of the lateral spread of light. , But has a slightly larger effective area. The exposed area of the photoresist layer 2 ′ also has a slightly larger effective area than the light passing area of the photomask 3 which is not shaded. However, in the exposed region of the photoresist layer 2 ′, the photoresist layer 2 is irradiated with light through the light passage restriction layer 61, and therefore, the irradiation of light is performed with a light amount smaller than that of the photoresist layer 62. As such, it has an effective area which is slightly smaller than the exposed area of the photoresist layer 62 '.

Next, a patterned photoresist layer 62 ″ having a pattern corresponding to the pattern of the photomask 3 is formed from the photoresist layer 62 ′ by etching the photoresist layer 62 ′ of the laminated body 63 ′ (first pattern).
(Figure D).

Next, the pattern having the same pattern as the patterned photoresist layer 62 ″ is formed from the light passage limiting layer 61 by etching the light passage limiting layer 61 of the laminated body 63 ′ using the patterned photoresist layer 62 ″ as a mask. An opticalized light passage limiting layer 61 'is formed (FIG. 1E).

Then, a patterned photoresist layer 2 ″ having a pattern corresponding to the pattern of the photomask 3 is formed from the photoresist layer 2 ′ by etching the photoresist layer 2 ′ of the laminated body 63 ′, and thus the pattern is obtained. The patterned photoresist layer 2 ″, the patterned light passage restriction layer 61 ′, and the patterned photoresist layer 61 ″ are laminated in this order to form a patterned laminate 63 ″ (FIG. 1F).

In this case, the exposed area of the photoresist layer 2'of the laminate 63 'has an effective area which is slightly smaller than the exposed area of the photoresist layer 62', and
Since the patterned light passage limiting layer 61 ′ is formed using the patterned photoresist layer 62 ″ as a mask, the patterned photoresist layer 2 ″ of the patterned laminate 63 ″ is formed.
Are formed to have side surfaces slightly outside the side surfaces of the patterned light passage restriction layer 61 ′ and the patterned photoresist layer 62 ″.

Next, by patterning the material of the target patterned layer on the substrate 1 by using the patterned laminate 63 ″ as a mask, patterning of the material of the target patterned layer is performed on the substrate 1. The layer 4 has a smaller thickness than the patterned laminate 63 ″, but the thickness of the patterned photoresist layer 2 ″ of the patterned laminate 63 ″ and the thickness of the patterned light passage limiting layer 61 ′. The target patterned layer is formed to a thickness thicker than the sum (FIG. 1G).

In this case, the patterned layer 4 includes a patterned layer portion 4a having a pattern inverted with respect to the patterned photoresist layer 2 ″, and a patterned light passage limiting layer formed on the patterned layer portion 4a. 61 ′ and a patterned layer portion 4 b having a pattern that is inverted with respect to 61 ′, and thus has a T-shaped cross section.

Then, the patterned photoresist layers 2 ″ and 62 ″ of the patterned laminate 63 ″ are removed by ablation treatment, so that the patterned photoresist layers 2 ″ and 62 ″ are removed, and thus the patterned photoresist layers 2 ″ and 62 ″ are removed. Layers 2 "and 62" and patterned light-passage limiting layer 61 'therebetween.
Are removed from the substrate 1, and finally, the patterned laminate 63 ″ is removed from the substrate 1 to obtain a structure in which the desired patterned layer 4 is formed on the substrate 1 ( (Fig. 1 H).

The above is the first embodiment of the patterned layer forming method according to the present invention.

According to such a patterned layer forming method of the present invention,
In the step of forming the patterned layer 4 (FIG. 1G),
The patterned layer 4 masks the patterned laminate 63 ″ in which the patterned photoresist layer 2 ″, the patterned light passage restriction layer 61 ′, and the patterned photoresist layer 62 ″ are laminated. Has a smaller thickness than the patterned laminate 63 ″ on the substrate 1, but is thicker than the sum of the thickness of the patterned photoresist layer 2 ″ and the thickness of the patterned light passage restriction layer 61 ′. The patterned photoresist layer 62 ″ may be formed to a large thickness, while the patterned photoresist layer 62 ″ may be formed to a large thickness, so that the patterned layer 4 is connected to the patterned layer 5 formed on the patterned photoresist layer 63. If the patterned laminate 63 ″ is removed from the substrate 1 to finally obtain the patterned layer 4 (FIG. 1H), the patterned layer 4 is not likely to be formed. Has a clear outline Obtained as having a turn.

Further, since the patterned layer 4 is formed in a T-shaped cross section, the gate electrode layer of the Schottky junction field effect transistor is formed as in the case of the conventional patterned layer forming method described above with reference to FIG. It has characteristics such as being suitable for application in some cases.

Second Embodiment Next, a second embodiment of the patterned layer forming method according to the present invention will be described with reference to FIG.

The first embodiment of the method for forming a patterned layer according to the present invention takes the following sequential steps to form a desired method for forming a patterned layer.

That is, the same substrate 1 as in the case of FIG. 3 is prepared in advance (FIG. 2A).

Then, on the substrate 1 of FIG.
Photoresist layer 71 having a negative type opposite to the positive type of
Then, a light-transmitting limiting layer 61 and a photoresist layer 72 made of the same material as the photoresist layer 71 are laminated in that order to form a laminate 73 (FIG. 2B).

In this case, as in the case of FIG. 1, the light passage restriction layer 61 allows the light used in the subsequent exposure processing to pass therethrough, but has a transmittance of less than 1 for the light, or similarly, Light that is used during the subsequent exposure process is transmitted, but when it is irradiated with the light, its transmittance changes toward the low or high direction. For example, it is a synthetic resin polymer into which a dye exhibiting photochronism is introduced. Consists of layers.

Next, a third pattern having a desired pattern for the stack 63 is formed.
By the exposure processing using the photomask 3 similar to that described above in the figure, the photoresist layer 71 ′ by the photoresist layer 7 exposed in the pattern corresponding to the pattern of the photomask 3 from the stacked body 63, and the light passage restriction. A layered body 73 'is obtained in which the layer 61 and the photoresist layer 72' by the photoresist layer 72 exposed to the pattern corresponding to the pattern of the photomask 3 are laminated in that order (FIG. 2C).

In this case, the exposed region of the photoresist layer 72 'of the stacked body 73' is wider than the light-passing region of the photomask 3 which is not shaded as shown by the hatching because of the lateral spread of light. , But has a slightly larger effective area. The exposed region of the photoresist layer 71 'also has a slightly larger effective area than the light-passing region of the photomask 3 which is not shaded. However, the photoresist layer 71 '
In the exposed area of the photoresist layer 71 ',
Light is irradiated through the light passage restriction layer 61, and therefore,
Since the photoresist layer 72 receives light with a smaller amount of light than the photoresist layer 72, it has a slightly smaller effective area than the exposed area of the photoresist layer 72 '.

Next, a patterned photoresist layer 72 ″ having a pattern in which the pattern of the photomask 3 is inverted is formed from the photoresist layer 72 ′ by etching the photoresist layer 62 ′ of the stacked body 73 ′ (FIG. 2). D).

Next, the pattern having the same pattern as the patterned photoresist layer 62 ″ is formed from the light-passage limiting layer 61 by an etching process using the patterned photoresist layer 72 ″ as a mask on the light-passage limiting layer 61 of the stacked body 73 ′. A converted light passage limiting layer 61 'is formed (FIG. 2E).

Next, by performing an etching process on the photoresist layer 2'of the laminated body 63 ', the photoresist layer 71' is removed.
Forming a patterned photoresist layer 71 ″ having a pattern that is the inverse of the pattern of the photomask 3, and
Patterned photoresist layer 72 ", patterned light passage restriction layer 61 ', and patterned photoresist layer 71".
And patterned laminate 7 in which and are laminated in that order
3 ″ is formed (FIG. 2F).

In this case, the exposed area of the photoresist layer 71 'of the laminate 73' has an effective area which is slightly smaller than the exposed area of the photoresist layer 72 ', and the patterned light passage restriction is performed. Since layer 61 'is formed using the patterned photoresist layer 72 "as a mask,
The patterned photoresist layer 71 ″ of the patterned laminate 73 ″ is formed as having a side surface slightly inside the side surfaces of the patterned light passage restriction layer 61 ′ and the patterned photoresist layer 72 ″.

Next, by patterning the material of the target patterned layer on the substrate 1 by using the patterned laminate 63 ″ as a mask, patterning of the material of the target patterned layer is performed on the substrate 1. Layer 4 to patterned photoresist layer 7
It is formed as a target patterned layer having a thickness smaller than that of 1 ″ (FIG. 2G).

Then, the patterned photoresist layers 71 ″ and 72 ″ of the patterned laminate 73 ″ are removed by ablation treatment to remove the patterned photoresist layers 71 ″ and 72 ″, and thus the patterned photoresist layers 71 ″ and 72 ″ are removed. The resist layers 71 ″ and 72 ″ and the patterned light passage restriction layer 61 ′ between them are removed from the substrate 1, and finally the patterned laminated body 73 ″ is removed from the substrate 1, and thus the substrate 1
A structure in which the desired patterned layer 4 is formed thereon is obtained (FIG. 2H).

The above is the first embodiment of the patterned layer forming method according to the present invention.

According to such a patterned layer forming method of the present invention,
The patterned laminated body 73 ″ is formed on the substrate 1 in a short time,
Since the patterned layer 4 can be easily removed, the patterned layer 4 can be easily formed in a short time.

[Brief description of drawings]

FIG. 1 is a schematic cross-sectional view in a sequential process showing a first embodiment of the patterned layer forming method according to the present invention. FIG. 2 is a schematic cross-sectional view in a sequential process showing a second embodiment of the patterned layer forming method according to the present invention. FIG. 3 is a schematic cross-sectional view in a sequential process showing an example of a conventional patterned layer forming method. FIG. 4 shows another example of the conventional patterned layer forming method,
It is an approximate line sectional view in a sequential process. FIG. 5 shows another example of the conventional patterned layer forming method,
It is an approximate line sectional view in a sequential process. FIG. 6 shows another example of the conventional patterned layer forming method,
It is an approximate line sectional view in a sequential process. FIG. 7 shows another example of the conventional patterned layer forming method,
It is an approximate line sectional view in a sequential process. 1 ... Substrate 2, 2 ', 62, 62' 71, 71 ', 72, 72' ...
Photoresist layer 3 Photomasks 2 ", 62", 71 ", 72" Patterned photoresist layer 4 Patterned layers 63, 63 ', 73, 73' Laminates 63 ", 73" ″ …… Patterned laminate 61 …… Light-passage limiting layer 61 ′ ... Patterned light-passage limiting layer

Claims (1)

[Claims] 1. A step of forming a first laminated body in which a first photoresist layer, a light passage limiting layer, and a second photoresist layer are laminated in that order on a substrate, and By the exposure process using a photomask having a desired pattern on the first laminate, the third photoresist is exposed to a pattern corresponding to the pattern of the photomask from the first laminate. A photoresist layer, the light passage limiting layer, and a fourth photoresist layer formed of the second photoresist layer exposed in a pattern corresponding to the pattern of the photomask are laminated in that order. The step of obtaining the second laminated body, and the etching treatment of the fourth photoresist layer of the second laminated body from the fourth photoresist layer to the photomask. A step of forming a first patterned photoresist layer having a pattern corresponding to the pattern, and an etching process for the light passage limiting layer of the second laminate using the first patterned photoresist layer as a mask A step of forming a patterned light passage limiting layer having the same pattern as the first patterned photoresist layer from the light passage limiting layer, and an etching treatment for the third photoresist layer of the second laminate. Forming a second patterned photoresist layer having a pattern corresponding to the pattern of the photomask from the third photoresist layer, thus providing the second patterned photoresist layer and the patterned light. A patterned product in which a passage limiting layer and the first patterned photoresist layer are laminated in that order. A patterned layer made of the above material is formed on the substrate by a step of forming a body and a deposition process of a material for the desired patterned layer on the substrate using the patterned laminate as a mask. And a step of removing the patterned laminate from the substrate by an ablation process for the patterned laminate.