JPS626650B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a semiconductor wafer cleaning apparatus.

In general, in a so-called dicing process in which a semiconductor wafer is cut into individual chips (pellets), cleaning the cut wafer after dicing is considered to be an essential operation. That is, fine silicon debris adheres to the surface of the cut wafer after dicing, and it is necessary to remove this silicon debris for subsequent steps.
In particular, the bonding pad on the wafer protrudes from the wafer surface more than other parts, and since the surface is made of aluminum with a relatively rough surface, silicon debris can spread to other parts. It tends to stick more than other materials. Bonding・
Adhesion of silicone debris on the pads may lead to defective wire bonding, leading to an increase in the defective rate of semiconductor devices, so it is said that the bonding pads in particular must be cleaned reliably. ing.

Conventionally, due to the above-mentioned requirements, ultrasonic cleaning devices have been used to clean wafers. This ultrasonic cleaning device irradiates the wafer with ultrasonic waves to separate silicon debris on the wafer from its surface, and although it was able to achieve its original purpose, it had the following problems. Something was clear. That is, diced wafers often break due to ultrasonic vibrations, and if the process includes dicing the wafer after fixing it on a thin film, even if the wafer is attempted to be ultrasonically cleaned, However, the ultrasonic vibrations are absorbed by the film, resulting in insufficient cleaning of the wafer, and the ultrasonic cleaning apparatus cannot be used even in such cases.

The present invention has been made in view of the above-mentioned circumstances, and includes a turntable having a rotation center axis and holding a semiconductor wafer, a drive device for rotationally driving the turntable, and a wafer on the turntable. a spray nozzle device rotatably supported and having a spray nozzle capable of sequentially spraying cleaning liquid and drying gas in a fan-like manner toward a surface; This spray is centered around the rotation center set approximately on the rotation axis of this turntable.
A rotating device for rotating a nozzle device in the opposite direction with respect to the turn table to rotate an injection area ejected from the injection port in a direction opposite to the rotation direction of the turn table. Since this is a cleaning device, the present invention provides a cleaning device for semiconductor wafers that can spray cleaning liquid and the like onto the wafer at extremely high speed and over a wide range, thereby reliably and quickly removing dirt on the wafer.

DESCRIPTION OF THE PREFERRED EMBODIMENTS A semiconductor wafer cleaning apparatus according to an embodiment of the present invention will be described below with reference to the drawings.

The figure shows a semiconductor wafer cleaning apparatus according to an embodiment of the present invention, and numeral 2 indicates a diced wafer. The wafer 2 is placed on a mounting surface of a turn table 6, and the turn table 6 is rotatably connected to a motor 4 serving as a drive device for rotating the turn table 6. The mounting surface of the turn table 6 is a surface perpendicular to the rotation center axis Y-Y' of the turn table 6. This turntable 6
has a variable rotation speed and a wafer holding mechanism that can reliably hold the wafer 2 on the wafer mounting surface. In the illustrated example,
This holding mechanism includes a relatively small hole 8 made on the wafer mounting surface, and a pipe 10 that communicates with the hole 8 and extends inside the turntable to a vacuum device.
By applying negative pressure to the opening 8, the wafer 2 is held by suction. On the turn table 6, a jet liquid is applied to the wafer 2.
A spray nozzle device 12 is positioned which can spray the high-pressure drying gas in a fan-like manner toward the wafer 2 and similarly spray the high-pressure drying gas in a fan-like manner toward the wafer 2 . This spray nozzle device 12 is eccentric from the rotation axis Y-Y' of the turntable, and moreover, the spray nozzle device 12 is rotated about a rotation center defined approximately on the rotation axis of the turntable 12. It is connected to a rotation device consisting of a support shaft 14, a spherical bearing 16, an eccentric cam, and a motor 22 for rotating the turntable 6 in the opposite direction. That is, this spray nozzle device 12
is attached to one end of a support shaft 14, and this support shaft 14 is configured such that the nozzle of the spray nozzle device 12 provided at one end thereof can rotate in a plane perpendicular to the Y-Y axis. It is supported by a spherical bearing 16. This support shaft 14 may be provided with a shaft length adjustment mechanism for adjusting the distance between the spray nozzle device 12 and the mounting surface of the turntable 6. A spherical portion 18 is provided at the other end of the support shaft 14, and this spherical portion 18 is rotatably attached to an eccentric cam 20 at a position eccentric from the central axis Y-Y' of the device. This eccentric cam 2
0 is connected to the motor 22. The amount of eccentricity of this eccentric cam 20 determines the inclination angle θ of the support shaft 14 with respect to the central axis Y-Y' of the device, and this angle θ
is determined based on the distance D from the spray nozzle 12 to the surface of the wafer 2 on the turn table 6, and the spray angle α of the spray nozzle device 12. These values are determined so that the jet liquid and gas sprayed in a fan shape from the spray nozzle device 12 hit the wafer 2 with appropriate strength and sufficiently cover the area of the wafer 2. ing. The spray nozzle device 12 includes a two-way solenoid valve 24 supplying a high-pressure gas, such as air or nitrogen, and a two-way solenoid valve 24 supplying running water and a high-pressure drying gas.
It is connected to a directional solenoid valve 26.
Said motor 4, 22 and solenoid valve 2
4 and 26 are controlled by a suitable timer device or programming device (not shown) based on the order of operation as described below.

In the semiconductor wafer cleaning apparatus configured as described above, a diced wafer or a wafer 2 fixed on a diced thin film is used.
is placed on the wafer placement surface of the turn table 6, and the vacuum device is activated to turn the wafer 2.
It is securely held on the table 6. Thereafter, the motors 4 and 22 are activated, and the turntable 6 and the spray nozzle device 12 begin their rotational movement. Since the turn table 6 and the spray nozzle device 12 rotate in opposite rotational directions as shown in the figure, the relative rotational movement between them becomes extremely high speed. Thereafter, the solenoid valves 24 and 26 are energized, so that the solenoid valve 2
4, high pressure gas is also supplied to the solenoid valve 26.
Flowing water is sent to the spray nozzle device 12, and from the nozzle of the spray nozzle device 12, an atomized jet stream is sprayed toward the wafer 2 in a fan shape. As already mentioned, the spray nozzle device 12 and the turntable 6
The wafer 2 is irradiated with a jet jet with strong cleaning power because the relative movement with the wafer is extremely fast, and since the jet jet is ejected in a fan shape, the cleaning action reaches every corner of the wafer. This jet liquid turns and turns with the silicon chips on the wafer.
Turn table 6 due to centrifugal force of table 6
It will be leaked outside. Once sufficient time has elapsed to remove silicon debris on the wafer,
The solenoid valve 24 is deenergized and the solenoid valve 26 is switched to a mode that supplies high pressure drying gas. The solenoid
The high pressure drying gas sent to the spray nozzle device 12 via the valve 26 is directed while removing any remaining liquid in the supply path, and
The ink is similarly ejected from the ejection opening of the nozzle device 12 toward the wafer 2 . The cleaning liquid remaining on the wafer 2 is removed by the centrifugal force of the turn table 6 and the high pressure drying gas. After sufficient time has elapsed for this purpose, the solenoid valve 2
6 is deenergized, and the operation of the motors 4 and 22 is stopped. Thereafter, the operation of the vacuum device is stopped, and the wafer 2 can be removed from the turntable 6, and cleaning of the wafer 2 is completed.

As described above, according to the present invention, there is provided a semiconductor wafer cleaning apparatus that can quickly and reliably clean wafers by high-speed cleaning.

[Brief explanation of the drawing]

FIG. 1 is a schematic diagram showing a semiconductor wafer cleaning apparatus according to an embodiment of the present invention. 2... Wafer, 4... Motor, 6... Turn table, 8... Hole, 10... Pipe, 12... Spray
Nozzle device, 14... Support shaft, 16... Spherical bearing,
18... Spherical part, 20... Eccentric cam, 22... Motor,
24...2-way solenoid valve, 26...3-way solenoid valve.

Claims (1)

[Claims] 1. A turntable having a central axis of rotation and holding a semiconductor wafer, a drive device for rotationally driving this turntable, and a fan-shaped jet of cleaning liquid and dry gas sequentially toward the wafer surface on the turntable. a spray nozzle device rotatably supported having a spray nozzle capable of spraying; and a rotation axis eccentric from the rotational axis of the turntable and defined substantially on the rotational axis of the turntable. Spray this around the center.
A rotating device for rotating a nozzle device in the opposite direction with respect to the turn table to rotate an injection area ejected from the injection port in a direction opposite to the rotation direction of the turn table. cleaning equipment.