JPH01243517A - Manufacture of semiconductor device - Google Patents

Abstract

PURPOSE:To make a semiconductor device rapidly at low cost, by transferring patterns to be transferred onto a photoresist at one time by using a photomask having two or more kinds of patterns. CONSTITUTION:For making a fine semiconductor integrated circuit pattern, a reticle 1 is used. Patterns a1 and b1 carried by a reticle 1 are transferred onto a photoresist on a wafer by a step-and-repeat transfer of a reduction projection exposure, to form a fine pattern. On the other hand, for making a rough pattern, a 1:1 photomask 2 is used. Patterns a2 and b2 carried by the 1:1 photomask 2 are transferred onto a photoresist on a wafer at one time by a 1:1 projection aligner, to make a rough pattern.

Description

Detailed Description of the Invention [Field of Industrial Application] The present invention relates to a technique particularly effective when applied to semiconductor manufacturing technology and the formation of semiconductor integrated circuits, and particularly relates to a technique effective when applied to lithography. It is something.

[Prior art] Regarding the phosphorography technology for patterning semiconductor integrated circuits, for example, see the electronic material special edition "Ultra LSI Manufacturing and Testing Equipment Guidebook J" published by the Kogyo Kenkyukai on November 20, 1985. It is described on pages 95 to 102.

When such a light exposure system is used as a lithography technique, reduction projection exposure and same-magnification exposure are used.

In reduction projection exposure, a pattern to be transferred having dimensions 5 or 10 times larger than the actual pattern is 2 times larger than the actual pattern.
A reticle carrying at least four reticles is used, and the pattern to be transferred carried by this reticle is transferred onto a photoresist on a wafer by a step-and-repeat method.

In addition, for 1:1 exposure, use a 1:1 photomask or 1:1 photomask.
:1 EB mask is used. Among these, the 1:1 water mask is manufactured using a reticle and carries a transferred pattern with the same dimensions as the actual pattern, while the 1:1 EB mask is manufactured using an electron beam. This EB mask also carries a transferred pattern having the same dimensions as the actual pattern. Then, use this 1:1 photomask and 1:1 photomask.
The EB mask for :1 simultaneously carries transfer patterns corresponding to the number of semiconductor devices on the wafer, and these transfer patterns are transferred to the photoresist at the same time. These photomasks (reticle, 1:1
Regarding the pattern accuracy in the 1:1 EB mask and the 1:1 EB mask, the reticle has the highest pattern accuracy, followed by the 1:1 EB mask and the 1:1 photomask. On the other hand, when it comes to pattern formation speed.

EB mask for 1:1 and photomask for 1:1 are fast,
The reticle is the slowest.

By the way, in conventional photomasks, all the transferred patterns within one photomask are the same. Furthermore, when forming one semiconductor integrated circuit pattern in a semiconductor device, one photomask set consisting of 15 or more photomasks is usually required; It consisted of a photomask. That is, for example, if it is a reticle, it is only the reticle, and if it is a 1:1 photomask, it is 1:1.
One photomask set consisted of only one photomask. When selecting these sets, a set consisting only of a reticle or a set consisting of a 1:1 EB mask is used when forming a semiconductor integrated circuit pattern consisting of a fine pattern that requires high resolution;
In forming a semiconductor integrated circuit pattern consisting of a relatively rough pattern (hereinafter referred to as a rough pattern), a set of 1:1 EB masks or a set of 1:1 photomasks has been used.

However, semiconductor integrated circuit patterns are not only made up of either a fine pattern or a rough pattern, but some are made up of both patterns. For example, in a microcomputer, the memory section is made up of fine patterns, and the calculation section is made up of rough patterns. In the formation of such semiconductor integrated circuit patterns, conventionally, a photomask set that matches a pattern (fine pattern) with higher required accuracy has been used.

[Problem to be solved by the invention] However, according to the manufacturing method as described above.

There were the following problems.

That is, conventionally, one photomask carries only transferred patterns corresponding to the same semiconductor device, which is inconvenient when manufacturing a wide variety of semiconductor devices in small quantities. That is, in order to manufacture a wide variety of semiconductor devices in small quantities, the only option is to form the various types of semiconductor devices on separate wafers, or to form many types of semiconductor devices on the same wafer. In either case, a photomask set is required for each semiconductor device, and the lithography process is performed separately, so □ semiconductor devices cannot be manufactured quickly and at low cost.

In addition, in the former case, surplus space is created on the wafer,
As a result, there is a drawback that the cost of the semiconductor device becomes even higher.

In addition, in the past, when manufacturing semiconductor devices with a mixture of fine and rough patterns, a photomask set and a regular reticle were used that matched the pattern (fine pattern) with higher accuracy requirements. The number of times the reticle and sample stage are moved relative to each other (step-and-repeat movement) when transferring the pattern to be transferred;
In other words, the number of steps increases, and it takes time to form a semiconductor integrated circuit pattern, which hinders the improvement of throughput in a semiconductor device manufacturing line. On the other hand, to improve throughput, 1:1 as a photomask
When using a set of 1:1 photomasks or a set of 1:1 EB masks, there is a drawback that high pattern accuracy cannot be obtained as described above, and the reliability of the semiconductor device decreases. The present invention was made in view of such conventional problems, and aims to provide a method of manufacturing a semiconductor device that can manufacture a highly reliable semiconductor device at low cost and quickly.

The above and other objects and novel features of the present invention will become apparent from the description of this specification and the accompanying drawings.

[Means for Solving the Problems] Representative inventions disclosed in this application will be summarized as follows.

In other words, one photomask set is composed of multiple types of photomasks with different accuracy, and the photomasks are replaced as needed depending on the required pattern accuracy.
The photoresist is designed to carry more than one type of transferred pattern, and to simultaneously transfer two or more types of transferred patterns onto the photoresist.

[Operation] According to the above-mentioned means, a photomask carrying a plurality of types of transferred patterns is used, and the transferred patterns are simultaneously transferred onto the photomask, so that various types of semiconductor devices can be simultaneously formed on the same wafer. Due to this effect, different types of semiconductor devices can be manufactured in small quantities, and even when manufacturing of a wide variety of semiconductor devices in small quantities is required, the wafer itself can be used effectively, which contributes to reducing the cost of semiconductor devices. Become. Further, when manufacturing different types of semiconductor devices, pre-processing can be performed simultaneously, so semiconductor devices can be manufactured quickly.

In addition, one photomask set is made up of multiple types of photomasks with different accuracy, and the photomasks are replaced at any time according to the required pattern accuracy, so semiconductor integrated circuit patterns can be quickly created according to the required pattern accuracy. Due to this effect, a highly reliable semiconductor device can be quickly obtained.

[Example] Hereinafter, an example of the method for manufacturing a semiconductor device according to the present invention will be described based on the drawings.

First, a photomask set used in the manufacturing method of the embodiment will be described. A photomask set consisting of a reticle 1 and a 1:1 photomask 2 shown in FIGS. 1 and 2 is used.

Here, the reticle 1 carries a pattern to be transferred which has dimensions five or ten times larger than the actual pattern, although this is not particularly limited. Transfer patterns all bi are drawn. The transferred patterns az+b correspond to fine patterns in two types of semiconductor devices, respectively.

On the other hand, the 1:1 photomask 2 carries a transferred pattern having the same size as the actual pattern, and on this reticle 1, the transferred pattern aft b corresponds to the number of semiconductor devices on the wafer. Only the minutes are drawn. This transferred' pattern 82tb2 corresponds to the rough patterns in the two types of semiconductor devices, respectively.

Next, a method of manufacturing a semiconductor device according to an embodiment using such a photomask set will be described.

Note that one photomask set includes a plurality of reticles and a plurality of 1:1 photomasks, and the following description will be made assuming that the above two photomasks are representative.

First, reticle 1 is used for fine patterns among semiconductor integrated circuit patterns. Then, the pattern to be transferred azyb1 carried on the reticle 1 is transferred onto the photoresist on the wafer by step-and-repeat movement using a reduction projection exposure apparatus, thereby forming a fine pattern.

On the other hand, a 1:1 photomask 2 is used for a rough pattern among the semiconductor integrated circuit patterns.

Then, a rough pattern is formed by transferring the transferred pattern azt bz carried on the 1:1 photomask 2 onto a resist on a wafer using an isostatic optical device.

According to the method for manufacturing a semiconductor device as described above, the following effects can be obtained.

That is, according to the above-described semiconductor device loading method, each photomask carries two or more types of transferred patterns, and the two or more types of transferred patterns are simultaneously transferred onto the photoresist, so that a large variety of products can be manufactured in small quantities. In the case of manufacturing a semiconductor device, the pre-processes, which were conventionally performed separately, can be performed at the same time, so that the semiconductor device can be manufactured quickly. In addition, when different types of semiconductor devices are formed on the same wafer in this way, the cost of the semiconductor devices can be reduced due to the effect that one wafer can be used effectively.

Further, according to the above-described semiconductor device manufacturing method, one photomask set is composed of two types of photomasks (reticle 1 and 1:1 photomask 2) with different accuracy, and the reticle is used in areas with high required pattern accuracy. 1 is used, and on the other hand, a 1:1 photomask is used in areas where the required pattern accuracy is low, so that a semiconductor integrated circuit pattern that meets the required accuracy can be formed quickly. In other words, when forming a semiconductor integrated circuit pattern that includes a mixture of fine patterns and rough patterns, it is no longer necessary to form the entire semiconductor integrated circuit pattern by reduction projection exposure, and the number of steps of reduction projection exposure can be reduced accordingly. , the throughput in the semiconductor device manufacturing line will be improved.

Although the invention made by the present inventor has been specifically explained above based on examples, it goes without saying that the present invention is not limited to the above-mentioned examples, and can be modified in various ways without departing from the gist thereof. Nor.

For example, in the above embodiment, a case was explained in which one photomask set consisting of a reticle and a 1:1 photomask was used, but one photomask set consisting of a reticle and a 1:1 EB mask, One photomask set consisting of an EB mask and a 1:1 photomask, or one photomask set consisting of a reticle, a 1:1 EB mask and a 1:1 photomask may be used.

In addition, the reticle and 1:1 photomask that carry two types of transferred patterns have been explained.
It may carry three or more types of transferred patterns.

[Effects of the Invention] The effects obtained by typical inventions disclosed in this application are briefly explained below.

That is, according to the present invention, a photomask set is composed of a plurality of types of photomasks having different accuracy, and the photomasks are sequentially replaced according to the required pattern accuracy, and each photomask is made to carry two or more types of transferred patterns. Since two or more types of transferred patterns are simultaneously transferred onto the photoresist, a highly reliable semiconductor device can be manufactured quickly and at low cost.

[Brief explanation of the drawing]

FIG. 1 is a plan view of a reticle used in an embodiment of the method for manufacturing a semiconductor device according to the present invention, and FIG. 2 is a 1:1 photomask used in an embodiment of the method for manufacturing a semiconductor device according to the present invention. FIG. 1... Reticle, 2... 1:1 photomask,
8□t 821 b, + b, ... Transferred pattern.

Claims (1)

[Claims] 1. Using a photomask set consisting of a plurality of photomasks that simultaneously carry transferred patterns corresponding to a plurality of semiconductor devices, the transferred patterns carried on each photomask are sequentially transferred. When transferring to photoresist on a wafer, the above-mentioned photomask set is composed of multiple types of photomasks with different accuracy, and the photomasks are replaced as needed according to the required pattern accuracy. 1. A method of manufacturing a semiconductor device, characterized in that a pattern to be transferred is supported and two or more types of patterns to be transferred are simultaneously transferred onto a photoresist. 2. The method for manufacturing a semiconductor device according to claim 1, wherein the one photomask set is composed of any two of a reticle, a 1:1 photomask, and a 1:1 EB mask. . 3. The method of manufacturing a semiconductor device according to claim 1, wherein the one photomask set includes a reticle, a 1:1 photomask, and a 1:1 EB mask.