JPS60119720A - Electron beam exposure - Google Patents

Abstract

PURPOSE:To obtain stably a picture having no streaky blotch when the pattern of the light receiving part of a charge transfer device for an image sensor provided repetitively with fundamental patterns of a large number is to be divided into fine sections of a large number at an electron beam exposure device by a method wherein the divided patterns are made to have a fixed repetition in the scanning direction of an electron beam, and moreover the pitch thereof is made to coincide with the pitch of the fundamental patterns. CONSTITUTION:The pattern of the light receiving part of a CCD is constituted of stripe type first patterns 11 stretching in the perpendicular direction to the scanning direction of an electron beam and cross-shaped second patterns 12 positioning between the formers, and the patterns thereof are repeated at a fixed pitch. While, an electron beam exposure device also divides the pattern into fine sections, the pattern is exposed to be drawn at every fine section thereof, and when the pattern of the light receiving part of the CCD is formed in such a way, butting error is not generated. At this construction, when the repetition pitch of the patterns 11, 12 is indicated by (a), and sizes of the fine sections 14, 15 in the scanning direction are indicated by (b), (c), sizes of the sections 14, 15 are decided as to satisfy the equation a=b+c.

Description

DETAILED DESCRIPTION OF THE INVENTION The pattern of the light-receiving part of the heavy transfer device used as an image sensor such as RRS, CCD, BBD, etc. of this invention can be used for the laser beam exposure device 2 (reticle material, photomask etc.). He is concerned with methods of exposing and drawing on blanks, IJ condensed wafers, etc.

1. Using an electron beam exposure device, the pattern of the light receiving part of the charge transfer device for an image sensor is exposed and drawn on a photomask blank or the like. I! ], similarly to other semiconductor circuit patterns, this pattern is divided into minute sections (for example, 256 .mu.fi x 2048 .mu.m topography), and the pattern table is drawn by scanning each section with an electron beam.

According to such an exposure drawing method, it is known that a pattern abnormality generally referred to as a batting error occurs at the boundaries of minute sections.

This batting error will be explained based on FIG. The micro sections 3.6.3 are divided at a pitch of 256 μm in the beam scanning direction depending on the function of the bar beam. 4
．． 4..., pattern abnormality 2.2.2... occurs. Pattern abnormality 2, 2.2... shown in Figure 1
The pattern appears in a protruding form at the boundary line, but other pattern abnormalities are also known, such as a depression in the boundary line or a pattern abnormality in which the boundary line curves in the vertical direction. Note that, of course, no pattern abnormality occurs in case A where no pattern exists on the boundary line. Such a pattern abnormality, that is, batting error 'r'!
, is a type of deformation of the pattern, but unlike 't'i disconnection or short circuit in general semiconductor integrated circuits such as memory, even if such deformation occurs, there is no problem in terms of performance, so it can be ignored. The current situation is that

However, the CCD used as an image sensor, B
The pattern of the light-receiving part of a charge transfer device such as a BD is a repeating basic pattern, and if this pattern is divided into minute sections and exposed and drawn as described above, depending on the type of pattern, it will be Batting errors may occur at regular intervals, and uneven streaks may be observed during visual inspection.

When a charge transfer device with such uneven streaks is used to take an image, the uneven streaks also occur on the display, which poses a major quality problem.

This invention has been made to solve the above-mentioned problems, and when a pattern (a repeating pattern of a basic pattern) of a light-receiving part of a direct transfer device is exposed and drawn using an electron beam exposure device, the pattern is Even with the repeating basic pattern, no uneven streaks were observed during visual inspection.

The object of the present invention is to provide an electron beam exposure method that does not visually cause uneven streaks even when both images obtained by photographing using this charge transfer device are projected on a display. be.

This invention was made to achieve this purpose.

We focused on the fact that even if uneven streaks occur due to batting errors, if they occur at a pitch so short that they cannot be discerned by the human eye, the user will no longer feel that uneven streaks exist visually, and as a means to do so, we used an electron beam. The repeating pattern is divided into minute sections so that it has a constant repetition in the scanning direction, and the repeating pitch of the minute sections in parentheses is the repeating pattern! 7) , Q This is an electron beam exposure method characterized by performing Trn light writing of a pattern by setting it to match the repetition pitch of the main pattern.

Hereinafter, the present invention will be explained in detail based on embodiments of the drawings.

FIG. 2 is an explanatory diagram of a pattern of a light receiving section of a CCD, which is a type of charge transfer device.

This pattern includes a striped first pattern 11 extending in a direction perpendicular to the child beam scanning direction, and a cross-shaped second pattern 12 existing between the first patterns. A first pattern 12 and a second pattern 13, which are basic patterns, are repeated at a constant pitch in the direction of the electron beam set meal. On the other hand, as mentioned above, the electron beam exposure apparatus divides the pattern into minute sections and exposes and draws the pattern for each minute section, so if a pattern exists on the boundary line between adjacent minute sections, the position of the pattern can be changed. A pattern abnormality occurs in
A batting error occurs.

With this invention, 1. Also, the pattern to be exposed and drawn is divided into minute sections so as to have a constant repetition in the scanning direction of the electron beam, and the repetition pitch of these minute sections is set to match the repetition pitch of the basic pattern 11 and 12. Thus, pattern abnormalities caused by batting errors always appear at a fixed position in the basic pattern.

In the embodiment shown in FIG. 2, the repetition pitch of the basic patterns 11.12 is a, and the microdivisions 14.12 are repeated at a pitch.
Assuming that the dimensions in the electron beam scanning direction of each of the micro sections 14 and 15 are '&b and c, the sizes of the micro sections 14 and 15 are determined so as to satisfy the relationship a = b + c.

As a result, the boundary line 17 between adjacent micro-divisions always exists at a certain position in the basic pattern 12, and therefore, a batting error = 13 always appears at this position, and no other batting errors appear.

It should be noted that the batting error r at the boundary line 16 "appears only in the upper and lower W:ij parts of Mako's first pattern 11,
It does not occur in the middle of the pattern as shown in FIG. Furthermore, by appropriately determining the phase and dimensions of the electron beam fences in the scanning direction of the minute sections 114 and 15, it is possible to set the pattern so that no pattern exists on the boundary line. No batting errors will occur.

In this example, since the repetition pitch a of the basic pattern is relatively long, for example 240 μm, for example b
If the repetition pitch a is sufficiently small, such as c = 128 μm and c = 112 μm, the micro-divisions may be set so that the dimension of one micro-division in the adult beam scanning direction matches the pitch of the basic pattern.

By setting minute divisions in this way, batting errors) will not occur at all, or even if they occur, they will be fixed at a fixed position in the basic pattern. Is it the same as the pitch of
It is possible to make it very small, smaller than C, making it impossible to visually determine the adverse effects of batting errors, and therefore, a charge transfer device with a pattern drawn by exposure in this way cannot be used for photographing. Even defects 1c, such as uneven streaks due to batting errors, are no longer recognized in the resulting images.

As described above, this invention is designed to ensure that the batting error, which is unique to electron beam exposure equipment, always occurs at a fixed position in a repeating pattern. 1. If there is an unevenness in the human eye because it occurs in a short period, 1. I don't feel it, so CCD.

If the pattern (repetitive pattern) of the light receiving part of a charge transfer device such as 13BD is exposed and drawn by the method of the present invention,
It is extremely effective because it does not cause abnormalities such as uneven streaks in the pattern itself, and can eliminate defects such as uneven streaks that occur in a single image taken using the charge transfer device. It is possible to stably produce patterns of good quality.

[Brief explanation of the drawing]

FIG. 1 is an explanatory diagram of batting errors that occur during pattern drawing using an electron beam exposure device. FIG. 2 is an explanatory diagram of an embodiment of pattern drawing by the method of this invention. 11.12...Basic pattern 1.1ro...Batting error, 14.15...Minute division, 16,17...
・Boundary line patent applicant Toppan Printing Co., Ltd. Representative Kazuo Suzuki 1, /1・

Claims (1)

[Claims] 1) An electron beam exposure device is used to divide the light-receiving part of a charge transfer device for an image sensor, which is composed of a large number of basic turns turned over, into a large number of minute sections, and then expose and draw them. According to the method described above, each minute section is divided so that it has a certain repetition in the scanning direction of the d-beam, and the repeated pinching of this minute section is the basic method described above. The pitch is set to match the pitch of the turn of the j falling light 1, 1 stillness (jii beggars)' (IT, the child beam 1.t is the original method.