Brush scrubbing apparatus

• US 6,330,728 B2
• Filed: 01/12/2001
• Issued: 12/18/2001
• Est. Priority Date: 03/09/1998
• Status: Expired due to Fees

• Current Assignee: Oki Semiconductor Company Limited (ROHM Co., Ltd.)
• Original Assignee: OKI Electric Industry Company Limited
• Inventors: Osako, Takashi, Ueki, Koji
• Primary Examiner(s): Spisich, Mark
• Application Number:
  US09/758,214
• Publication Number:
  US 20010001886A1
• Time in Patent Office: 340 Days
• Field of Search: 15/211, 15/77, 15/881, 15/884, 15/971, 151/02
• US Class Current: 15/77
• CPC Class Codes: B08B 1/32 using rotary cleaning members
• CPC Class Codes: H01L 21/67046 using mainly scrubbing means, e.g. brushes

Abstract

A brush scrubbing apparatus is made up of a wafer holder which retains a wafer, a brush which removes a particle on the wafer, a driver which rotates at least one of the wafer holder and the wafer, an alignment mechanism which defines a relative position between the brush and the wafer holder, and controller which controls the alignment mechanism responding to a driving power supply voltage in the driver. The brush scrubbing apparatus can precisely get the reference position for deciding the pushing distance without using the eye measurement.

Claims

1. A brush scrubbing apparatus, comprising:

a rotating turntable which retains a wafer;

a brush which removes a particle on the wafer;

driving means for driving the brush through the use of a driving current; and

a controller which detects a reference position of said brush responding to a change of a first current value for driving the brush, the change being caused by the brush contacting the wafer, said controller further storing a predetermined distance to thrust said brush downward from the reference position, said controller also storing a second current value for driving the brush when the brush is moved downward toward the wafer until the predetermined distance to thrust said brush downward from the reference position is reached, said controller finding a differential value between the first and second current values and comparing the differential value and a predetermined threshold value;

wherein the reference position is a position in which the brush contacts the wafer.

2. A brush scrubbing apparatus as claimed in claim 1, further comprising:

a wafer rotating apparatus which includes the rotating turntable which horizontally retains the wafer and which turns on a vertical axis, and a wafer spin motor;

a first voltage supply circuit which supplies power to the wafer spin motor;

a nozzle which supplies a cleaning solution to a surface of the wafer;

a brush spin mechanism which rotates the brush, and which includes a brush spin motor, a driving shaft as a driving axis of the brush spin motor, a driving gear which is mounted to the driving shaft, a brush shaft to operate the brush, a gear to operate the brush shaft, and a transmission belt which connects between the driving gear and the gear;

an arm;

an arm mechanism which retains the brush;

an arm swing mechanism which swings the arm;

an arm up and down mechanism which moves the arm up and down; and

a second voltage supply circuit which supplies power with a power supply voltage line to the brush spin mechanism.

3. A brush scrubbing apparatus as claimed in claim 2, wherein the cleaning solution is a deionized water.

4. A brush scrubbing apparatus as claimed in claim 2, wherein the predetermined threshold value is a permissible range for a change from the current value at the reference position, and when the differential value is more than the threshold value, the arm mechanism controls responding to the differential value so that the driving current value during the scrubbing step is made equal to the reference current.