JPS59144126A - Manufacture of semiconductor device - Google Patents

Abstract

PURPOSE:To realize quick and highly accurate alignment by forming a pattern in the area near the circumference of wafer and vacuum-depositing electrode metal by covering this pattern with the sawl part of planetarium at the time of vacuum-depsiting electrode metal. CONSTITUTION:An alignment pattern 11 is formed in the area near the circumference in the right and left of a semiconductor wafer 10. A planetarium 13 has a hole 14, a stepped part 15 where the wafer 10 is placed by positioning around the hole 14 and a pawl part 16 which is extended toward the center of hole 14 from two areas of right and left sides of such stepped part 15. When the wafer 10 is placed by positioning on the stepped part 15, the pawl part 16 covers the pattern 11. Under this condition, an electrode metal such as aluminum is vacuum-deposited from the lower side. Next, a photo resist film is coated on the wafer 10 and alignment is carried out by confirming the pattern 11 through such film.

Description

DETAILED DESCRIPTION OF THE INVENTION Technical Field The present invention relates to a method for manufacturing a semiconductor device, and more specifically, a method for performing mass 2 alignment for patterning electrode metal using an alignment pattern formed on a semiconductor wafer as a reference. Regarding.

BACKGROUND ART When manufacturing semiconductor devices, the time and accuracy of alignment between a mask and a semiconductor wafer are important because several photoetching processes are repeated. For this reason, conventionally, as shown in FIG. 1, alignment patterns 2, 2 are formed on the left and right sides of a semiconductor wafer 1, and alignment is automatically performed using these alignment patterns 2, 2 as a reference. These alignment patterns 2, 2 are formed by photoetching an oxide film,
As shown in FIG. 2, a protrusion 3°3 with a height of about 0.1 to 1.2P or a groove with a depth of about 0.1 to 1.2μ is formed on the surface 1a of the semiconductor wafer zl. has been done.

However, when depositing the electrode metal, the fir electrode metal 4 is deposited on the alignment patterns 2, 2 as shown in FIG. It is necessary to check and perform alignment, but the surface of the electrode metal 4 is too reflective,
Not only is it difficult to confirm the alignment patterns 2, 2 due to the small gap between the tops of the protrusions 3 and other parts, but also, as can be seen from FIG.
The width of the protrusions 4a, 4a of the electrode metal 4 on ゜3 is wider than the width of the protrusions 3, 3, and the protrusions aa, 4a on the L side are continuous with the remaining portion on the inclined surface, so the alignment pattern 2 ,2
It becomes extremely difficult to confirm the alignment, resulting in a long alignment time and low accuracy.

DISCLOSURE OF THE INVENTION Therefore, an object of the present invention is to provide a method for manufacturing a semiconductor device that allows rapid and highly accurate alignment during alignment for patterning electrode metal.

In summary, the present invention can be summarized by forming an alignment pattern near the peripheral edge of a semiconductor wafer, covering this alignment pattern with a claw part of a planetarium during vapor deposition of electrode metal, and then vapor depositing electrode metal. This method is characterized in that the alignment for patterning the electrode metal is performed based on the uncovered alignment pattern.

That is, since the oxide film or semiconductor material does not have a high reflectance at the edge of the electrode metal, the contrast between the protrusions or grooves of the alignment pattern and the remaining parts is large, and furthermore, since the alignment pattern is not covered by the electrode metal, It is easy to confirm the alignment pattern, and alignment can be performed quickly and with high precision.

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, one embodiment of the present invention will be described with reference to FIGS. 4 to 8.

FIG. 4 is a plan view of the semiconductor wafer. Figure 5 is a bottom view of the main part of the planetarium, and Figure 6 is the W--
FIG. 3 is a cross-sectional view taken along the Vi line. FIG. 7 is an enlarged sectional view of the main part of the semiconductor wafer after electrode metal deposition. FIG. 8 is an enlarged sectional view of the main part of the semiconductor wafer after the photoresist film is formed.

In this invention, first, as shown in FIG. 4, alignment gaps 11 and 11 are formed near the left and right peripheral edges of the semiconductor wafer 10. This alignment.

Next, this alignment pattern 11. Alignment work in several photo-etching steps is performed using ll as a reference.

When depositing the electrode metal, a planetarium 13 having the shape shown in FIGS. 5 and 6 is used. That is, this planetarium 13 has a hole 14, a stepped portion 15 on which the semiconductor wafer 1o is placed with its entire position positioned around the hole 14, and this stepped portion 1.
It has claw portions 16, 16 that extend toward the center of the hole 14 from two places on the left and right sides of the hole 14. When the semiconductor wafer 10 is positioned and placed on the stepped portion 15, the claw portions 16,
16 covers the alignment pattern l'l, 11.

In this state, when an electrode metal such as aluminum is deposited from below, an alignment pattern 1 is formed as shown in FIG.
Next, as shown in FIG. 8, a photoresist film 18 is coated on this semiconductor wafer lO, and the alignment pattern 1.11 is passed through the photoresist film 18. Confirm Yu 1 8
71 and perform alignment.

At this time, the electrode metal 17 is not formed on the alignment pattern 11.11, and the photoresist film 18 is transparent and has a thickness of 0.7 to 1.1 mm. Since it is approximately Q/j, the alignment pattern 11.11 can be checked easily and reliably, and the alignment work can be performed quickly and with high accuracy.

[Brief explanation of drawings]

FIG. 1 is a plan view of a semiconductor wafer having a conventional alignment pattern. FIG. 2 u is an enlarged sectional view of the alignment pattern portion of the semiconductor wafer of FIG. 1; FIG. 3 is an enlarged sectional view of the same alignment pattern portion after forming the electrode metal. FIG. 4 is a plan view of a semiconductor wafer on which an alignment pattern of the present invention is formed. FIG. 5 is a main bottom view of a planetarium for electrode metal deposition used in the present invention. FIG. 6 is a sectional view of the main part of the planetarium shown in FIG. 5, taken along line M-M. FIG. 7 is an enlarged cross-sectional view of the alignment pattern portion on the semiconductor knee after electrode metal deposition according to the present invention. FIG. 8 is an enlarged sectional view of the alignment pattern portion on the semiconductor wafer after the formation of the photoresist film. 10...Semiconductor wafer, 11...Alignment turn, 12...
... Protrusion, 13 ... Planetarium, 16 ... Claw portion, 17 ... Electrode metal, 18 ... Photoresist film.

Claims (1)

[Claims] A method for manufacturing a semiconductor device in which an alignment pattern is formed on a semiconductor wafer and alignment is performed using the alignment pattern, comprising: forming the alignment pattern near the peripheral edge of the semiconductor wafer; The method is characterized by comprising a step of vapor depositing an electrode metal by covering it with a claw portion of a planetarium, and a step of performing alignment for patterning the electrode metal based on the alignment pattern not covered by the tM gold metal. A method for manufacturing a semiconductor device.