JPS58155304A - Size measuring device - Google Patents

Abstract

PURPOSE:To make it possible to perform highly accurate measurement of the size of a minute pattern in a short time, by providing a constitution wherein a table on which an object to be measured can be moved between the first and second pattern detecting parts, and the amount of the movement can be measured. CONSTITUTION:The XYtheta table 1 is moved and a part of the material to be measured A is set at the center of the first pattern detecting part 2. At this time, the position of the XYtheta table 1 is inputted to a control part 12 by a length measuring machine 11. The control part 12 outputs a signal, by which the XYtheta table 1 is moved rightward by a distance l between both detecting parts 2 and 3 with said position as a reference, to a controller 13. Thus, the part to be measured of the material to be measured, which is set at the center of the first pattern detecting part 2 is moved to the right as a unitary body with the XYtheta table, and positioned at the center of the second pattern detecting part 3. At the second pattern detecting part 3, an electron beam is immediately scanned and the pattern detection is performed. Thus the size of the pattern of the desired part can be measured with high resolution quickly and a highly accurately.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention is a dimension selection method* that is effective for determining the dimension of a pattern formed on a photomask or wafer for semiconductor MS circuits.
It is related to.

With the miniaturization of semiconductor integrated circuit devices in recent years,
The dimensions of the circuit patterns formed on photomasks and wafers are also reduced to 2 to 1.6 micrometers or less, and the pattern dimensions are also adjusted to reduce the risk of serious damage to the L7T integrated amii.
It is necessary to determine the pattern width dimension for I# and manage it so that it falls within a certain range. Conventionally, as a device for scooping out such pattern dimensions, an optical method 1ii has been used.
t is often used, and the t method using a T17 camera and the method using a laser spora) 1 are common. Bone K
The i1 device focuses the laser light on a small spot and ll1iji! When the object pattern is scanned, the scattered light that is lost at the edge of the object pattern is captured and captured by the pattern edge in! It has the advantage that the dimensions are determined using the laser spot scan length, stage (object) amount, and sound, and the accuracy is high.

However, in these devices, the wavelength of light (about 0.5μ) is the wavelength of light (due to the usage of light),
Therefore, when determining the pattern size @kffiii, it is necessary to measure the step dimension 11 of the pattern edge portion, which is measured by scooping out this step dimension from a layer that is 0.5 pm or less. For this reason, in the past, the measurement field for the pattern is Due to the same measurement accuracy, it is extremely narrow, and as a result, the workability of searching for the measurement point of the pattern is poor, and it takes a long time to assemble the molding device, making it impractical.

Therefore, it is an object of the present invention to install a first pattern detection section using light and a second pattern detection section using electron beams, and to install a table t on which an object to be measured is placed. By configuring so that seven sgmtrms can be determined by moving between the first and second pattern detection sections, p1
Dimension measurement eel cage that can measure moldy burn dimensions in a short time and in a% tank j[K! I provide KToru.

The present invention will be explained below based on the illustrated example.

Figure 1 is a structural diagram of the metal body of the device of the present invention.
Pattern detection lI2 and 2 pattern detection @3 and ten! Sekigamite'tLl! i12 is running. The irises 1 pern detector 2 disposed on the left side 111 in the figure is equipped with a light 4, a bar filler 5, a plurality of lenses 6, and a light receiving element 7 such as a linear image sensor or a solid-state camera. The light from 1 is reflected by the bar filler l5Vc, and the light from X! - OVa constant (wafer, photomask) work surface on table 1
On the other hand, the reflected light from the surface [half-solar svt is transmitted to the light-receiving element 7, and this causes 61
The pattern on the surface of the column 1 constant object can be detected over an extremely wide gap. 17t, the second one placed on the right glue as shown in the figure.
Pattern detection 1! I3 is electron beam generation 418 and electron beam detection! It is a scanning electron II with 1iF9 and t, and is emitted from the electron beam generator 8 and IN
Detecting the electron beam reflected by the surface of the object to be measured using the electron beam detection 419.
C. Patterns can be detected in a narrow range or at high resolution.

On the other hand, said X! -Table 1 is a part of its upper surface;
p*ie*au constant A
1 line 20 burn detector 2.10 It should be possible to detect by any one of them. It was! Y# One head of table l is equipped with 1ttl of length measurement using laser light, and at least
! - It is possible to measure the amount of movement of the table 1 in the horizontal direction shown in the drawing.

And, this elongated machine 110g constant output is the above-mentioned III.

The output of the second Pern detector 2.3 is inputted to the calculation function 11 section 12. A controller 13 for driving the XY table 1 is controlled by a signal from the octopus control section 12. In the figure, 1
It is a 4-division display or record.

According to the above configuration, first! ! -Table l'YrSS
Reference target 1ot - 1st pern detection 1tsi
Detected at 12, this 1! :Kino table position [slender 1
111 and stored in control s12. Next,!
! - table it is moved to the right (reference targetera) i0kl1
2 pa#-y test ff1i13? Detection aiL, the table position at this time is input to the ttw control section 12.

As a result, the control unit 12 detects the difference between the extensions during the calculation period Ltltldetectff1l$2.1.

Next, move the part of the II scooping object you want to measure (xxl table 1kll) and set it at the center of the first pattern detection section 2. In this case, since the first pattern detection section 2 has a relatively wide detection field of view, This positioning can be done very easily and quickly.

At this time, xY# table l position at-a length 1
1111 to the control unit 12, and the control unit 12 calculates the interval 1 between the two detection units 2.3 based on this *1 - standard.
Output the signal t to the controller 13 to set xY# table lk right movement'':1.

The Australian 61J constant mPfr of the class measurement object set at the center of the first pattern detection section 2 is X! - It is moved to the right front integrally with the table and positioned at the center of the second pattern detection Sa. Therefore, if the second pattern detection section 3 immediately uses the electron beam for pattern detection, the
Pattern dimension of the spot - 1 Constant r High WI! High accuracy K in marriage degree
And it can be done quickly.

Incidentally, (2) shows the wafer W [the signal output for one dimension of the formed pattern WP is shown in Figure 2].

Here, the distance l between the two pattern detectors 2 and 3 is fixed and only needs to be measured once at the beginning. Australian measurement point WI'gr setting work and subsequent control 11 part 12,
All that is required is the automatic position setting operation and automatic dimension measurement operation by the controller 13, and the Il! It will be short or short. In addition, when setting the position of the fixed location of Australia l#I to the first pattern detection section, the XY# table 11rY direction (
It may be moved in the direction perpendicular to the plane of the paper) or in the θ direction. Furthermore, a T'V camera may be used for the first pattern detection gain 2.

As described above, according to the size determination apparatus of the present invention, there are a first bar detector 7 using light, a two-pattern detector using an electron beam Since the table is used to measure and pray for the moving field and its moving type, if you measure in advance at the gate 114 of each pattern detector in the collection 11, you can obtain a temporary measurement knowledge. After setting the measurement point Pkk in the specified position of the pattern detection part, it is possible to automatically complete the dimension shelf of 714fIIIiL, thereby quickly determining the pattern dimension 11r in pagIInt. It has the effect of being able to do things.

[Brief explanation of the drawing]

Figure 1 shows the dimensions of the present invention! ! Fig. 2 (B) is an explanatory diagram of the measurement flaw, 53) is a cross-sectional view of the measurement signal, and 53) is a cross-sectional view of the wrinkle. DESCRIPTION OF SYMBOLS 1...XYθ table, 2...1st pattern detection section, 3...fg2 pattern detection section, 10...Group S target, 11...Shin Uinaga, 12...System@@, 13・
··controller.

Claims (1)

[Claims] 1. Comparative K11 constant field range wide I/kI using light [8]
I! A pattern detection section, a high-resolution two-pattern detection section used for the electron beam,
It is assumed that the present invention is provided with a table that operates 5Sll between the pattern detection sections of the table, an oscillation for detecting the movement position tr of this table, and a control aS for controlling the movement of the table tS based on the table position signal from this sub-situation. Size 15i
! Column c is fixed.