JPS62144332A - Aluminum spin-spray etching device - Google Patents

Abstract

PURPOSE:To prevent the residue of aluminum etching even in a pattern having directional properties, and to conduct etching uniformly by using a motor, which can be turned reversely, as a spinning motor rotating a body to be etched during etching. CONSTITUTION:A photo-resist is applied onto an aluminum film formed onto a semiconductor wafer 3 consisting of silicon, a mask for a desired pattern is baked by using a projection exposure device, the pattern to be etched is developed, the wafer 3 is placed on a spinning chuck 2 and the spinning chuck 2 is revolved, and an etching liquid is sprayed to the wafer 3 from a nozzle 8 and a film to be etched is etched. Since the spinning chuck 2 is turned forward and reversely, there is no reside of aluminum etching, and the film to be etched can be etched uniformly. Accordingly, the shortage of etching and over-etching are removed, thus eliminating the need for re-etching while improving yield by equal etching.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a semiconductor device manufacturing apparatus, and more particularly to a wet etching apparatus for an aluminum film layer on a semiconductor wafer.

[Conventional technology]

Conventionally, this type of aluminum spin spray etching apparatus has an etching chamber that includes a nozzle that spouts an etching liquid, a spincher that rotates a semiconductor wafer that is an object to be etched, and an end point sensor that detects the end point of 11σ of an object to be etched. It consists of a washing chamber for washing etching liquid remaining on the object to be etched, and a drying chamber for drying the wet object to be etched after being washed with water. Then, a resist film of a predetermined number of turns is deposited on the surface of an object to be etched, such as an aluminum film on a semiconductor substrate, placed on a spin chuck, and the area to be etched is exposed. While the object to be etched is rotated in the same direction, the area to be etched is etched by spraying an etching liquid from a nozzle onto the object.

[Problem that the invention seeks to solve]

When etching an aluminum film layer, which is an object to be etched, on a semiconductor wafer, the above-mentioned conventional aluminum spin spray etching apparatus applies an etching solution onto the object while rotating the object to be etched once in the same direction using a spin chuck. It has a light structure that is sprayed from a nozzle and etched.

Therefore, for example, if the resist grooves 21 deposited on the aluminum film on the semiconductor wafer 3 are aligned parallel to the orientee/canal flat 24 as shown in FIG. 2, the spin motors can only move in the same direction. If it does not rotate, the etching solution will escape along the side surface 26 of the part to be etched, as shown in FIG. 3, and aluminum will remain on the opposite side surface 27. In addition, the remaining parts to be etched due to liquid leakage due to rotation can be reduced by lowering the rotation speed of the spin motor, but as shown in Figure 5, uniformity within the semiconductor wafer is 80Or, p, m~1000r
, pom has a coefficient of about 2, but when it becomes 400r, p, m, there is a drawback that it deteriorates to about 8%.

SUMMARY OF THE INVENTION The object of the present invention is to solve the above-mentioned drawbacks and provide an etching apparatus that can perform uniform etching faithfully to the resist pattern.

[Means for Solving the Problems] The present invention provides an apparatus for etching a semiconductor wafer, which is an object to be etched, by placing it on a spin chuck and spraying an etching liquid onto the wafer from a nozzle while rotating the wafer. This is an aluminum spin spray etching device characterized by having a motor that rotates the object to be etched in forward and reverse directions.

〔Example〕

Next, an embodiment of the present invention will be described with reference to the drawings.

FIG. 1 shows an embodiment of the present invention. In the figure, 1 is an etching chamber. The etching chamber 1 is provided with a spin chuck 2 for rotating a semiconductor wafer 3 as an object to be etched, a nozzle 8 for spraying an etching solution, and transmission type sensors 7a and 7b for determining the etching end point of a film to be etched. ing.

A timing belt 5 is passed between the spin shaft 4 of the spin chuck 2 and a spin motor 6 for forward and reverse rotation, and by rotating the spin shaft 4 with the motor 6, the spin chuck 2 can be rotated in the forward or reverse direction. Reverse. Nozzle 8, PTFE cheese 9, valve 10, solenoid valve 11
, are connected to an etching liquid tank 13 via a pump 12. The washing chamber 14 includes a washing shower 15 for washing away the etching solution on the semiconductor wafer after etching.
A conveyor belt 16 for conveying the wafer is installed. The drying chamber 17 is still provided with an air knife 18 for blowing dry air onto the surface of the semiconductor material to dry the wet semiconductor material after washing with water, and a water absorption roll 19 for removing moisture from the back surface of the material.

According to the aluminum spin spray etching apparatus configured in this way, for example, as shown in FIG. After aligning with the wafer 3 and printing a mask with a desired pattern using a projection exposure device to develop and print the pattern 22 to be etched, the wafer 3 is placed on the spin chuck 2 and the spin chuck 2 is rotated. Then, the etching liquid is sprayed from the nozzle 8 thereto to etch the film to be etched. According to the present invention, the spincher, Ri2
is rotated forward and backward as shown in Figure 4 (25, 28
), aluminum, and can be etched evenly without leaving any etching residue. When performing this etching, by operating the transmission type sensors 7a and 7b, which are end-boin sensors, when the etching of the film to be etched is completed, the rotation of the spin chuck and the spraying of the etching solution are stopped, and the etching is completed. do.

After that, the semiconductor wafer 3 is moved to the washing chamber 14, and while the semiconductor wafer 3 is being transported by the conveyor belt 16, the washing spray 1 is applied.
In step 5, spray pure water to wash away the etching solution and perform cleaning. After that, the wafer enters a drying chamber, and the air knife 18 blows dry air onto the semiconductor wafer surface to dry the wafer surface, and at the same time, the water absorption roll 19 absorbs moisture from the back surface of the wafer to dry the wafer.

〔Effect of the invention〕

As explained above, the present invention uses an aluminum spin spray etching apparatus that uses a reversible motor as a spin motor to rotate the object to be etched during etching, thereby removing the resist that has been baked onto the film to be etched on the semiconductor wafer. Even if the material has a directional pattern, it can be etched evenly without leaving any aluminum etching residue.This eliminates under-etching and over-etching, eliminating the need for re-etching. This has the effect of improving yield through uniform etching.

[Brief explanation of drawings]

Fig. 1 is a longitudinal cross-sectional view showing an embodiment of the present invention, Fig. 2 is a view showing a semiconductor urchin baked by Rennoston Nontar/., and Fig. 3 is a view showing the etched part when rotated in the same direction. FIG. 4 is a diagram showing the etched portion when rotated in the same direction and in the reverse direction, and FIG. 5 is an etching characteristic diagram. l...Etching chamber, 2...Spincher, 3.
・Wafer in half 4, ・1... spin shaft, 5...
・Timing belt, 6... Spin motor, 7a, 7
b... Transmission type sensor, 8... Spray nozzle, 9...
...PTFE f use, 10...rate valve for air, 11...magnetic valve, 12...pump, ]3...
・Etching liquid tank, 14...Washing room, 15...Washing shower, 16...Transport belt, 17...Drying room,
18...Air knife, 19...Water absorption roll, 21
...Renos l-122...Bunching, turning iP turn, 23...Alignment turning, 24...Orientation/Nyonalfla, l-125...Spin motor forward rotation direction, 26...・Etched turn side, 27
...Aluminum removal remains, 28...Spin motor reverse direction. Agent: Patent attorney Naka Kanno',t-,,,・
, l-Goichi; Figure 4

Claims (1)

[Claims] (1) An apparatus that performs etching by placing a semiconductor wafer, which is an object to be etched, on a spin chuck and spraying an etching solution onto the wafer from a nozzle while rotating the wafer, which includes a motor that rotates the spin chuck in forward and reverse directions. Features aluminum spin spray etching equipment.