KR20070014613A - Method for manufacturing semiconductor device - Google Patents

Abstract

A method of manufacturing a semiconductor device is provided to acquire an exact uniform alignment signal from wafers by using a scattering bar vertical to an alignment key. A scattering bar(110) is formed on a semiconductor substrate(100). A dielectric film(120) is formed along an upper surface of the resultant structure. An alignment key(130) is formed on the dielectric film. The scattering bar is formed by etching partially the substrate. The scattering bar is capable of being formed on the substrate. The alignment key is formed like a line/space type structure. The scattering bar crosses the alignment key. The scattering bar has the same width as that of the alignment key.

Description

Method for manufacturing a semiconductor device {METHOD FOR MANUFACTURING SEMICONDUCTOR DEVICE}

1 and 2 are a cross-sectional view and a graph showing a method for manufacturing a semiconductor device according to the prior art.

3A and 3B are a cross-sectional view and a plan view showing a method for manufacturing a semiconductor device according to the present invention.

4 is a cross-sectional view showing a method for manufacturing a semiconductor device according to the present invention.

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of manufacturing a semiconductor device, wherein a scattering bar is formed on a semiconductor substrate so as to be perpendicular to the direction of the alignment key between the lattice patterns of the alignment keys so that a bad signal reflected by the insulator of the semiconductor substrate is vertically aligned. Can be scattered to prevent detection so that accurate and uniform alignment signals can be obtained within or between wafers. Thus, overlay accuracy is increased and represents a technique for improving device properties and yields.

1 and 2 are cross-sectional views and graphs showing a method of manufacturing a semiconductor device in the prior art.

Referring to FIG. 1, after forming the insulating film 20 on the semiconductor substrate 10 in the scribe region, an alignment key 30 is formed. Here, 'A' represents the distance between the alignment key 30 and the semiconductor substrate 10, the thickness becomes uneven as the deposition process, the CMP process and the like. Therefore, there is a problem that the overlay is changed in or between wafers.

Referring to FIG. 2, a key used in wafer alignment of an exposure process is formed in a scribe region, which performs an alignment process using two lasers, red light (633 nm) and green light (532 nm). In this case, since the wavelength is changed depending on the thickness between the alignment key and the semiconductor substrate, two lasers are used to perform alignment by selecting a good signal among the two lasers.

In the above-described method of manufacturing a semiconductor device, there is a problem in that the thickness of the alignment key on the semiconductor substrate is not uniform, which is not accurate when the alignment signal is in or between wafers, and the accuracy of the overlay is deteriorated. .

In order to solve the above problem, a scattering bar is formed on the semiconductor substrate so as to be perpendicular to the direction of the alignment key between the lattice patterns of the alignment keys, so that a bad signal reflected by the insulator of the semiconductor substrate is scattered in the vertical direction to be detected. By doing so, accurate and uniform alignment signals can be obtained in or between wafers. Accordingly, an object of the present invention is to provide a method for manufacturing a semiconductor device in which the overlay accuracy is increased and the device characteristics and yield are improved.

Method for manufacturing a semiconductor device according to the present invention

Forming a scattering bar on the semiconductor substrate,

Forming a dielectric film on an entire surface of the semiconductor substrate including the scattering bar;

Forming an alignment key on the dielectric layer

Characterized in that it comprises a.

Hereinafter, with reference to the accompanying drawings an embodiment of the present invention will be described in detail.

3A and 3B are plan views and cross-sectional views illustrating a method of manufacturing a semiconductor device in accordance with a first embodiment of the present invention, and FIG. 3A is a cross-sectional view illustrating a cut line taken along line BB ′ of FIG. 3B.

Referring to FIGS. 3A and 3B, the scattering bar 110 is formed by etching the semiconductor substrate 100 on the scribe lane region to a predetermined depth, and then the dielectric layer 120 is formed on the semiconductor substrate 100. do.

Next, an alignment key 130 having a line / space shape is formed on the dielectric film 120.

Here, the scattering bar 110 is preferably formed to intersect the alignment key 130 in order to disperse the signal reflected on the semiconductor substrate 100, more preferably formed to have an angle of 90 °.

The interference between the reflected signal and the alignment signal is not caused, and the entire width of the scattering bar 110 is formed to be the same as that of the alignment key 130, and is formed in a size of 0.1 to 2 μm.

In addition, the pitch of the alignment key 130 and the scattering bar 110 is formed in a ratio of 1: 0.5 to 2 to adjust the scattering angle of the signal reflected from the semiconductor substrate 200.

4 is a cross-sectional view illustrating a method of manufacturing a semiconductor device in accordance with a second embodiment of the present invention.

Referring to FIG. 4, a first dielectric layer 210 is formed on the semiconductor substrate 200, and a scattering bar 220 is formed on the first dielectric layer 210.

Next, after forming the second dielectric layer 230 on the entire surface of the semiconductor substrate 200 including the scattering bar 220, an alignment key 240 having a line / space shape is formed on the second dielectric layer 230. .

Here, the scattering bar 220 is preferably formed to intersect the alignment key 240, more preferably formed to have an angle of 90 ° and to correspond to the space area between the alignment key 240 It is preferable.

In addition, the pitch of the alignment key 240 and the scattering bar 220 is formed in a ratio of 1: 0.5 to 2 to adjust the scattering angle of the signal reflected from the semiconductor substrate 200.

In the method of manufacturing a semiconductor device according to the present invention, a scattering bar may be formed on a semiconductor substrate in a form perpendicular to an alignment key to obtain a constant and accurate alignment signal within a wafer or between wafers. Therefore, the overlay accuracy is increased and the characteristics and the yield of the device are improved.

In addition, a preferred embodiment of the present invention is for the purpose of illustration, those skilled in the art will be able to various modifications, changes, substitutions and additions through the spirit and scope of the appended claims, such modifications and changes are the following claims It should be seen as belonging to a range.

Claims (8)

Forming a scattering bar on the semiconductor substrate; Forming a dielectric film on an entire surface of the semiconductor substrate including the scattering bar; And Forming an alignment key on the dielectric layer; Method of manufacturing a semiconductor device comprising a. The method of claim 1, The scattering bar is a semiconductor device manufacturing method, characterized in that formed by etching the semiconductor substrate to a predetermined depth. The method of claim 1, The scattering bar is a manufacturing method of a semiconductor device, characterized in that formed on the semiconductor substrate. The method of claim 1, The alignment key is a manufacturing method of a semiconductor device, characterized in that formed in the form of a line / space. The method of claim 4, wherein And the scattering bar is formed to intersect the alignment key. The method of claim 1, The scattering bar is a semiconductor device manufacturing method, characterized in that formed in the same width as the alignment key. The method of claim 1, The scattering bar is a manufacturing method of a semiconductor device, characterized in that formed in the size of 0.1 to 2μm. The method of claim 1, The pitch of the alignment key and the scattering bar is formed in a ratio of 1: 0.5 to 1.2.

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