← Back to Patent Explorer
US5643406A Expired / Lapsed US ⏱️ 0.0 years remaining

Chemical-mechanical polishing (CMP) method for controlling polishing rate using ionized water, and CMP apparatus

Assignee: Toshiba Corp
•
Filing: 1996-06-12
•
Granted: 1997-07-01
•
Expires: 2016-06-12
📄 Original PDF 🌐 Google Patents 🔄 Sync Now

Abstract

Abstract This invention provides a CMP (Chemical-Mechanical Polishing) method for controlling the polishing rate using ionized water and a CMP apparatus which employs the CMP method. A polishing pad is attached to a polishing disc. A semiconductor wafer is held by a wafer carrier placed above the polishing disc, and is pressed by the wafer carrier against the polishing pad which rotates together with the polishing disc. As a result, the semiconductor wafer is polished. The polishing is performed while a polishing slurry containing polishing particles is supplied to the polishing pad from a polishing slurry tank through a polishing-slurry supply pipe, and ionized water is supplied thereto through an ionized-water supply pipe. In the case of using alkaline ionized water as the ionized water, the polishing rate can be increased in a stable manner by increasing the pH value of alkaline ionized water, and can be reduced in a stable manner by reducing the pH value of alkaline ionized water. On the other hand, in the case of using acidic ionized water as the ionized water, the polishing rate can be increased in a stable manner by reducing the pH value of acidic ionized water, and can be reduced in a stable manner by increasing the pH value of acidic ionized water.

Inventors

  • 👤 Mariko Shimomura
  • 👤 Naoto Miyashita
  • 👤 Hiroyuki Ohashi

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-02 06:18
CPC Classifications
H; H10; H10P; H10P52/00; H10P52/40; H10P52/403; B; B24; B24B; B24B37/00; B24B37/04; B24B57/00; B24B57/02; C; C09; C09K; C09K3/00; C09K3/14; C09K3/1454; C09K3/1463; H10P90/00; H10P90/12; H10P90/129

Claims Analysis

Total Claims: 29
Claim 1
Independent Claim 68 words
A CMP method of chemically mechanically polishing a semiconductor wafer, comprising: a polishing step of polishing a to-be-polished film formed on the semiconductor wafer using a polishing pad, while supplying a working area of the polishing pad with a polishing slurry containing polishing particles; and a supply step of supplying ionized water created by electrolyzing deionized water, to a major surface of the semiconductor wafer obtained after polishing.
Claim 2
Dependent Claim 68 words
A CMP method of chemically mechanically polishing a semiconductor wafer, comprising: a polishing step of polishing a to-be-polished film formed on the semiconductor wafer using a polishing pad, while supplying a working area of the polishing pad with a polishing slurry containing polishing particles; and a supply step of supplying ionized water created by electrolyzing deionized water, to a major surface of the semiconductor wafer obtained after polishing.
Claim 3
Dependent Claim 21 words
The CMP method according to claim 1, wherein the ionized water is one of alkaline ionized water and acidic ionized water.
Claim 4
Dependent Claim 22 words
The CMP method according to claim 1, further comprising the treatment step of neutralizing a wasted water created in the polishing step.
Claim 5
Dependent Claim 34 words
The CMP method according to claim 3, wherein the ionized water is alkaline ionized water, and in the treatment step, the wasted water created in the polishing step is neutralized by acidic ionized water.
Claim 6
Dependent Claim 34 words
The CMP method according to claim 3, wherein the ionized water is acidic ionized water, and in the treatment step, the wasted water created in the polishing step is neutralized by alkaline ionized water.
Claim 7
Dependent Claim 33 words
The CMP method according to claim 3, wherein in the supply step, the ionized water is acidic ionized water when the to-be-polished film formed on the semiconductor wafer is made of a metal.
Claim 8
Dependent Claim 48 words
The CMP method according to claim 3, wherein in the supply step, the ionized water is one of alkaline ionized water and acidic ionized water when the to-be-polished film formed on the semiconductor wafer is made of one of an oxide, a nitride, polycrystalline silicon and monocrystalline silicon.
Claim 9
Dependent Claim 75 words
A CMP method of chemically mechanically polishing a semiconductor wafer, comprising: a supply step of supplying a polishing pad for polishing the semiconductor wafer with ionized water created by electrolyzing deionized water, and with a polishing slurry containing polishing particles; and a polishing step of polishing that major surface of the semiconductor wafer which has a to-be-polished film formed thereon, using the polishing pad, the polishing step being executed while the supply step is executed.
Claim 10
Dependent Claim 75 words
A CMP method of chemically mechanically polishing a semiconductor wafer, comprising: a supply step of supplying a polishing pad for polishing the semiconductor wafer with ionized water created by electrolyzing deionized water, and with a polishing slurry containing polishing particles; and a polishing step of polishing that major surface of the semiconductor wafer which has a to-be-polished film formed thereon, using the polishing pad, the polishing step being executed while the supply step is executed.
Claim 11
Dependent Claim 29 words
The CMP method according to claim 8, wherein in the supply step, the ionized water and the polishing slurry are supplied to the polishing pad through different supply means.
Claim 12
Dependent Claim 44 words
The CMP method according to claim 8, wherein the ionized water and the polishing slurry will reach those portions of the polishing pad, which are located close to each other and the distance between which is smaller than the diameter of the semiconductor wafer.
Claim 13
Dependent Claim 30 words
The CMP method according to claim 8, wherein in the supply step, the ionized water and the polishing slurry is mixed with each other before they reach the polishing pad.
Claim 14
Dependent Claim 21 words
The CMP method according to claim 8, wherein the ionized water is one of alkaline ionized water and acidic ionized water.
Claim 15
Dependent Claim 22 words
The CMP method according to claim 8, further comprising the treatment step of neutralizing a wasted water created in the polishing step.
Claim 16
Dependent Claim 34 words
The CMP method according to claim 6, wherein the ionized water is alkaline ionized water, and in the treatment step, the wasted water created in the polishing step is neutralized by acidic ionized water.
Claim 17
Dependent Claim 34 words
The CMP method according to claim 6, wherein the ionized water is acidic ionized water, and in the treatment step, the wasted water created in the polishing step is neutralized by alkaline ionized water.
Claim 18
Dependent Claim 17 words
The CMP method according to claim 8 or 13, wherein the ionized water has its temperature controlled.
Claim 19
Dependent Claim 93 words
A chemical-mechanical polishing (CMP) apparatus comprising: a polishing pad for polishing a semiconductor wafer; a polishing disc having the polishing pad mounted thereon, and to be rotated by a driving shaft; a wafer carrier for holding the semiconductor wafer and pressing against the polishing pad that major surface of the semiconductor wafer which has a film to be polished; an ionized-water supply pipe for supplying the polishing pad with ionized water created by electrolyzing deionized water; and a polishing-slurry supply pipe for supplying the polishing pad with a polishing slurry containing polishing particles.
Claim 20
Dependent Claim 93 words
A chemical-mechanical polishing (CMP) apparatus comprising: a polishing pad for polishing a semiconductor wafer; a polishing disc having the polishing pad mounted thereon, and to be rotated by a driving shaft; a wafer carrier for holding the semiconductor wafer and pressing against the polishing pad that major surface of the semiconductor wafer which has a film to be polished; an ionized-water supply pipe for supplying the polishing pad with ionized water created by electrolyzing deionized water; and a polishing-slurry supply pipe for supplying the polishing pad with a polishing slurry containing polishing particles.
Claim 21
Dependent Claim 32 words
The CMP apparatus according to claim 17, wherein the ionized-water supply pipe and the polishing-slurry supply pipe are movable so that they can be opposed to voluntary portions of the polishing pad.
Claim 22
Dependent Claim 26 words
The CMP apparatus according to claim 17, wherein the ionized-water supply pipe and the polishing-slurry supply pipe have their supply ports formed integral with each other.
Claim 23
Dependent Claim 44 words
The CMP apparatus according to claim 17, further comprising: an envelope receiving the polishing disc; a wasted-water pipe connected to the bottom of the envelope; and a one-way valve for preventing a wasted water from reversely flowing from the wasted-water pipe to the envelope.
Claim 24
Dependent Claim 34 words
The CMP apparatus according to claim 17, further comprising: an envelope receiving the polishing disc; a wasted-water pipe connected to the bottom of the envelope; and a sediment bath connected to the wasted-water pipe.
Claim 25
Dependent Claim 37 words
The CMP apparatus according to claim 17, further comprising: an electrolytic bath for electrolyzing the deionized water, the electrolytic bath being connected to the ionized-water supply pipe; and an ionized-water exhaust pipe connected to the electrolytic bath.
Claim 26
Dependent Claim 86 words
The CMP apparatus according to claim 17, further comprising: an electrolytic bath for electrolyzing the deionized water, the electrolytic bath being connected to the ionized-water supply pipe; an ionized-water exhaust pipe connected to the electrolytic bath; an envelope receiving the polishing disc; a wasted-water pipe connected to the bottom of the envelope and also to the ionized-water exhaust pipe; a one-way valve for preventing a wasted water from reversely flowing from the wasted-water pipe to the envelope; and a sediment bath connected to the wasted-water pipe.
Claim 27
Dependent Claim 23 words
The CMP apparatus according to claim 17, wherein the ionized-water supply pipe and the polishing-slurry supply pipe are formed of a teflon-based material.
Claim 28
Dependent Claim 21 words
The CMP apparatus according to claim 17, wherein the ionized water is one of alkaline ionized water and acidic ionized water.
Claim 29
Dependent Claim 19 words
The CMP apparatus according to claim 17, further comprising a mechanism for controlling the temperature of the ionized water.

References Cited (Backward Citations)

US5320706A Cited
US5516346A Cited
US5551986A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 2000-06-30 2000-12-30 2001-07-01 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 2004-06-30 2004-12-30 2005-07-01 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2008-06-30 2008-12-30 2009-07-01 $7700.00 Window Closed / Lapsed

Assigned Categories & Tags

No categories assigned to this patent yet.

Assign Category Tag