US5384682A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Electrostatic chuck
Assignee: Toto Ltd
•
Filing: 1993-03-22
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Granted: 1995-01-24
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Expires: 2013-03-22
Abstract
Abstract An electrostatic chuck has a substrate, an insulating layer disposed on the substrate for attracting a workpiece thereto, and an electrode interposed between the substrate and the insulating layer. The insulating layer having a volume resistivity ρ(Ωm), a dielectric constant ε r , and a thickness d (m), and being spaced from the workpiece which is attracted thereto by a gap having a distance δ(m). The volume resistivity ρ, the dielectric constant ε r , the thickness d, and the distance δ satisfy the following relationship: 1.731×10.sup.-11 ρ{ε.sub.r +d/δ}<60.
Inventors
- 👤 Toshiya Watanabe
- 👤 Tetsuo Kitabayashi
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 20:56
CPC Classifications
H; H02; H02N; H02N13/00; H10; H10P; H10P72/00; H10P72/70; H10P72/72; Y; Y10; Y10T; Y10T279/00; Y10T279/23
Claims Analysis
Total Claims: 16
Claim 1
Independent Claim
121 words
An electrostatic chuck comprising a substrate, an insulating layer disposed on said substrate for attracting a workpiece thereto, and an electrode interposed between said substrate and said insulating layer, said insulating layer having a volume resistivity ρ(Ωm), a dielectric constant ε r at a normal temperature of usage of the electrostatic chuck, and a thickness d (m), and being spaced from the workpiece which is attracted thereto by a gap having a distance δ(m), said volume resistivity ρ, said dielectric constant ε r , said thickness d, and said distance δ satisfying the following relationship: 1.731×10.sup.-11 ρ{ε.sub.r +d/δ}<60 so that a residual electrostatic force of the electrostatic chuck on a workpiece will be rapidly reduced at said normal temperature of usage.
Claim 2
Dependent Claim
121 words
An electrostatic chuck comprising a substrate, an insulating layer disposed on said substrate for attracting a workpiece thereto, and an electrode interposed between said substrate and said insulating layer, said insulating layer having a volume resistivity ρ(Ωm), a dielectric constant ε r at a normal temperature of usage of the electrostatic chuck, and a thickness d (m), and being spaced from the workpiece which is attracted thereto by a gap having a distance δ(m), said volume resistivity ρ, said dielectric constant ε r , said thickness d, and said distance δ satisfying the following relationship: 1.731×10.sup.-11 ρ{ε.sub.r +d/δ}<60 so that a residual electrostatic force of the electrostatic chuck on a workpiece will be rapidly reduced at said normal temperature of usage.
Claim 3
Dependent Claim
34 words
An electrostatic chuck according to claim 1, wherein said insulating layer is made of a sintered ceramic material comprising alumina, titania or chromia, and a silicon oxide or an oxide of alkaline earth metal.
Claim 4
Dependent Claim
37 words
An electrostatic chuck according to claim 1, wherein said insulating layer is made of a sintered ceramic material comprising Si 3 N.sub. 4 SiC, AlN, ZrO 2 , SiO 2 .Al 2 O 3 , or BN.
Claim 5
Dependent Claim
17 words
An electrostatic chuck according to claim 1, wherein said insulating layer is made of an organic rubber.
Claim 6
Dependent Claim
17 words
An electrostatic chuck according to claim 4, wherein said organic rubber includes chloroprene rubber or acrylic rubber.
Claim 7
Dependent Claim
16 words
An electrostatic chuck according to claim 1, including a protective film disposed on said insulating layer.
Claim 8
Dependent Claim
19 words
An electrostatic chuck according to claim 1, wherein said electrostatic chuck is adapted to attract a silicon workpiece thereto.
Claim 9
Dependent Claim
86 words
An electrostatic chuck comprising a substrate, an insulating layer disposed on said substrate for attracting a workpiece thereto, an electrode interposed between said substrate and said insulating layer, and a protective film disposed on said insulating layer, said insulating layer having a volume resistivity ρ and said protective film having a volume resistivity ρ t , said volume resistivities ρ, ρ t satisfying the following relationship: ρ.sub.t /ρ>10.sup.-1 so that sufficient electrostatic forces may be generated by the electrostatic chuck to securely attract a workpiece thereto.
Claim 10
Dependent Claim
86 words
An electrostatic chuck comprising a substrate, an insulating layer disposed on said substrate for attracting a workpiece thereto, an electrode interposed between said substrate and said insulating layer, and a protective film disposed on said insulating layer, said insulating layer having a volume resistivity ρ and said protective film having a volume resistivity ρ t , said volume resistivities ρ, ρ t satisfying the following relationship: ρ.sub.t /ρ>10.sup.-1 so that sufficient electrostatic forces may be generated by the electrostatic chuck to securely attract a workpiece thereto.
Claim 11
Dependent Claim
30 words
An electrostatic chuck according to claim 8, wherein said protective film is made of a ceramic material comprising Si 3 N 4 , SiC, SiO 2 , or the like.
Claim 12
Dependent Claim
34 words
An electrostatic chuck according to claim 8, wherein said protective film is made of a material of high thermal conductivity selected from a group comprising Al 2 O 3 , AlN, and C (diamond).
Claim 13
Dependent Claim
31 words
An electrostatic chuck according to claim 8, wherein said protective film is made of a material that is mainly composed of the material of said insulating layer which is highly purified.
Claim 14
Dependent Claim
104 words
An electrostatic chuck comprising a substrate, an insulating layer disposed on said substrate for attracting a workpiece thereto, and an electrode interposed between said substrate and said insulating layer, said insulating layer having a volume resistivity ρ(Ωm), a dielectric constant ε r , a thickness d (m), and a surface roughness (Rmax)esc (m), and the workpiece having a surface roughness (Rmax)plate (m), said volume resistivity ρ, said dielectric constant ε r , said thickness d, and said surface roughnesses (Rmax)esc, (Rmax)plate (m) satisfying the following relationship: ##EQU7## so that a residual electrostatic force of the electrostatic chuck on a workpiece will be rapidly reduced.
Claim 15
Dependent Claim
104 words
An electrostatic chuck comprising a substrate, an insulating layer disposed on said substrate for attracting a workpiece thereto, and an electrode interposed between said substrate and said insulating layer, said insulating layer having a volume resistivity ρ(Ωm), a dielectric constant ε r , a thickness d (m), and a surface roughness (Rmax)esc (m), and the workpiece having a surface roughness (Rmax)plate (m), said volume resistivity ρ, said dielectric constant ε r , said thickness d, and said surface roughnesses (Rmax)esc, (Rmax)plate (m) satisfying the following relationship: ##EQU7## so that a residual electrostatic force of the electrostatic chuck on a workpiece will be rapidly reduced.
Claim 16
Dependent Claim
16 words
An electrostatic chuck according to claim 9, including a protective film disposed on said insulating layer.
References Cited (Backward Citations)
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