Material for purification of semiconductor polishing slurry, module for purification of semiconductor polishing slurry and process for producing semiconductor polishing slurry

• US 20060205325A1
• Filed: 03/18/2004
• Published: 09/14/2006
• Est. Priority Date: 03/18/2003
• Status: Active Grant

• Current Assignee: Nomura Micro Science Co.,Ltd.
• Original Assignee: Nomura Micro Science Co.,Ltd.
• Inventors: Ito, Osamu, Abe, Mitsugu, Ogitsu, Masaaki, Nambu, Nobuyoshi, Inomata, Kazuo
• Granted Patent: US 7,625,262 B2
• Time in Patent Office: Days
• US Class Current: 451/36
• CPC Class Codes: B01J 45/00 Ion-exchange in which a complex or a chelate is formed; Use of material as complex or chelate forming ion-exchangers; Treatment of material for improving the complex or chelate forming ion-exchange properties ion-exchange chromatography processes B01D15/36
• CPC Class Codes: B01J 47/127 in the form of filaments or fibres
• CPC Class Codes: B24B 37/00 Lapping machines or devices; Accessories B24B3/00 takes precedence
• CPC Class Codes: B24B 57/02 for feeding of fluid, sprayed, pulverised, or liquefied grinding, polishing or lapping agents
• CPC Class Codes: C23F 1/46 Regeneration of etching compositions

Abstract

A material for purification of a semiconductor polishing slurry that without changing of pH value, is capable of efficiently purifying a polishing slurry to thereby not only prevent metal contamination of a polished object as effectively as possible but also achieve recycling of a polishing slurry without any problem; a relevant module for purification of a semiconductor polishing slurry; and a process for purifying a semiconductor polishing slurry with the use thereof. In particular, a material for purification of a semiconductor polishing slurry characterized in that it comprises a fibrous substrate having a functional group capable of forming a metal chelate or such a functional group together with hydroxyl fixed onto at least the surface thereof. This material for purification of a semiconductor polishing slurry is, for example, used in such a manner that it is inserted in a container fitted with polishing slurry inflow port and outflow port while ensuring passage of polishing slurry flow.

Claims

1. A material for purification of a semiconductor polishing slurry which is used to remove metals present in the semiconductor polishing slurry, comprising:

a functional group capable of forming a metal chelate;

a fibrous substrate of which at least the surface is fixed onto by the functional group.

4. A material for purification of a semiconductor polishing slurry according to any of claims 1 to 3,

wherein the fibrous substrate is at least one selected from a plant-based natural fiber, an animal-based natural fiber, a cellulose-based regenerated fiber and a polyvinyl alcohol-based synthetic polymer fiber.

5. A material for purification of a semiconductor polishing slurry according to any of claims 1 to 4, which is used to remove metals present in the semiconductor polishing slurry,

wherein the functional group capable of forming a metal chelate is at least one group selected from a group containing aminocarboxylic acids, a group containing phosphoric acids, a group containing thio compounds and a group with at least a part of acid type functional groups of these groups determined as alkali metal salt or ammonium salt.

6. A material for purification of a semiconductor polishing slurry, which is used to remove metals present in the semiconductor polishing slurry according to any of claims 1 to 5,

wherein the functional group capable of forming a metal chelate is a group containing amines or hydroxylamines.

7. A material for purification of a semiconductor polishing slurry used to remove metals present in the semiconductor polishing slurry,

wherein two or more of the materials for purification of the semiconductor polishing slurry having a different substrate and/or functional group among the materials for purification of a semiconductor polishing slurry according to any of claims 1 to 6 are laminated to form a layer or mixed.

8. A material for purification of a semiconductor polishing slurry used to remove metals present in the semiconductor polishing slurry,

wherein the material for purification of a semiconductor polishing slurry according to any of claims 1 to 6 is formed into a self-supportable sheet or felt.

9. A module for purification of a semiconductor polishing slurry,

wherein the material for purification of a semiconductor polishing slurry according to any of claims 1 to 8 is charged in a container provided with an inflow port and an outflow port for the polishing slurry so as to allow the polishing slurry to flow through it.

10. A module for purification of a semiconductor polishing slurry,

wherein the material for purification of a polishing slurry according to any of claims 1 to 8 is disposed in a flowable state within an area partitioned by a filter or a strainer through which the polishing slurry flows in a container provided with an inflow port and an outflow port for the semiconductor polishing slurry.

11. A process for purification of a semiconductor polishing slurry, comprising:

passing an object semiconductor polishing slurry through at least one of the material for purification of a semiconductor polishing slurry according to claims 1 to 8 or the module for purification of a semiconductor polishing slurry according to claims 9 and 10 to remove metals present in the object semiconductor polishing slurry;

supplying all of the object semiconductor polishing slurry to a step of polishing a semiconductor after removing the metals present in it;

or

after introducing at least a part or all of it to the original semiconductor polishing slurry and circulating again, supplying any of them to the step of polishing semiconductor.

12. A process for purification of a semiconductor polishing slurry according to claim 11,

wherein when a semiconductor polishing slurry being purified is acidic, an acid type end group of a functional group capable of forming a metal chelate is determined as an acid type (H type), and

when the polishing slurry being purified is alkaline, an acid type end group of a functional group capable of forming a metal chelate is determined as alkali metal salt or ammonium salt, and the object semiconductor polishing slurry is passed through at least one of the material for purification of a semiconductor polishing slurry according to any of claims 1 to 8 or the module for purification of a semiconductor polishing slurry according to claims 9 and 10 to remove metals present in the object semiconductor polishing slurry.

13. A process for purification of a semiconductor polishing slurry according to claim 11 or 12,

wherein when the object semiconductor polishing slurry is alkaline, the acid type end group of the functional group capable of forming the metal chelate is determined as alkali metal salt or ammonium salt which is a main component showing alkalinity of the object semiconductor polishing slurry.

14. A process for purification of a semiconductor polishing slurry according to any one of claims 11 to 13,

wherein pH of the semiconductor polishing slurry is adjusted before purification to decrease a change in the pH of the purified semiconductor polishing slurry.

2. A material for purification of a semiconductor polishing slurry which is used to remove metals present in the semiconductor polishing slurry, comprising:

a functional group capable of ion-exchanging with a hydroxyl group or capable of forming a metal chelate;

a fibrous substrate of which at least the surface is fixed onto by the functional group.

3. A material for purification of a semiconductor polishing slurry according to claim 2,

wherein the hydroxyl group is an ethylenical hydroxyl group and fixed onto the surface of the fibrous substrate in a hydroxyl value of 40 mg KOH/g or more.