Electrochemical polishing solution, process for electrochemically polishing graphite gate electrode and graphite gate electrode

Patent metadata

Field	Value
Publication number	US-9551085-B2
Application number	US-201414316302-A
Country	US
Kind code	B2
Filing date	Jun 26, 2014
Priority date	Feb 28, 2014
Publication date	Jan 24, 2017
Grant date	Jan 24, 2017

Abstract

The invention discloses an electrochemical polishing solution, a process for electrochemically polishing a graphite gate electrode and a graphite gate electrode, which are used for providing an electrochemical polishing solution and a polishing process to efficiently remove the contaminant on the surface of a gate electrode and improve the quality of the gate electrode. Said electrochemical polishing solution comprises 900-1000 parts by weight of water; 195-205 parts by weight of an alkaline metal hydroxide; 49-51 parts by weight of a weak acid salt; and 294-306 parts by weight of an additive.

First claim

What is claimed is:

1. A process for electrochemically polishing a graphite gate electrode, comprising the steps of:
placing an anode and a cathode into an electrochemical polishing solution and providing an electric current to the anode and the cathode to carry out the electrochemical polishing, wherein a graphite gate electrode is used as the anode, and a conductive metal or an alloy electrode is used as the cathode, and the electrochemical polishing solution comprises:
900-1000 parts by weight of water;
195-205 parts by weight of an alkaline metal hydroxide;
49-51 parts by weight of a weak acid salt; and
294-306 parts by weight of an additive for inhibiting the dissolution of the anode.

2. The process according to claim 1 , wherein providing the electric current to the anode and cathode to carry out the electrochemical polishing comprises providing an electric current of 160±5 amperes to the anode and cathode, wherein the duration of providing the electric current is 3-5 min and the temperature of the electrochemical polishing solution during the polishing is 90±5° C.

3. The process according to claim 1 , further comprising the steps of:
washing the electrochemically polished graphite gate electrode with water;
cleaning the graphite gate electrode washed with water in an ultrasonic cleaning device for 50-60 min; and
subjecting the graphite gate electrode cleaned by the ultrasonic cleaning device to dewatering treatment.

4. The process according to claim 3 , wherein subjecting the graphite gate electrode to dewatering treatment comprises cleaning the graphite gate electrode cleaned by the ultrasonic cleaning device with an alcohol.

5. The process according to claim 4 , wherein subjecting the graphite gate electrode to dewatering treatment further comprises blow-drying the graphite gate electrode cleaned with an alcohol by high pressure air or a hair drier.

6. The process according to claim 1 , wherein the parts by weight of the alkaline metal hydroxide are 200 parts by weight, the parts by weight of the weak acid salt are 50 parts by weight, and the parts by weight of the additive for inhibiting the dissolution of the anode are 300 parts by weight.

7. The process according to claim 1 , wherein the alkaline metal hydroxide is a sodium hydroxide or potassium hydroxide.

8. The process according to claim 1 , wherein the weak acid salt is potassium hydrogen fluoride or potassium chromate.

9. The process according to claim 1 , wherein the additive is glycerine.

Assignees

• Boe Technology Group Co Ltd
• Beijing Boe Vacuum Tech Co Ltd

Inventors

• Liao Meiling

Classifications

• H01J19/38

  Control electrodes, e.g. grid · CPC title

• H01J9/14

  of non-emitting electrodes · CPC title

• C25F3/30

  of semiconducting materials · CPC title

• C25F3/16 Primary

  Polishing · CPC title