# US 2021/0242046 A1 · Ceramic heater

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- Number: US 2021/0242046 A1
- Document ID: US20210242046A1
- Status: Published application
- Kind: A1
- Application number: 17/098,804
- Filed: 2020-11-16
- Published: 2021-08-05
- Earliest claimed: 2020-02-04
- Assignees: NGK Insulators, Ltd.
- Applicants: Ngk Insulators, Ltd.
- Inventors: Daichi KUBOTA; Norifumi SHIMAZU
- Web page: https://patentgrep.com/patent/US20210242046A1

## CPC

- H10P 72/0432: {mainly by conduction}
- H01J 37/32082: {Radio frequency generated discharge (H01J37/32357, H01J37/32366, H01J37/32394 and H01J37/32403 take precedence)}
- H01J 37/32724: {Temperature}
- H05B 1/0233: {for semiconductors manufacturing}
- H05B 3/283: {the insulating material being an inorganic material, e.g. ceramic}
- H10P 72/722: {Details of electrostatic chucks}
- H10P 72/7611: {characterised by edge profile or support profile}
- H01J 2237/2007: Holding mechanisms
- H01J 2237/3321: CVD [Chemical Vapor Deposition]
- H05B 2203/005: using multiple resistive elements or resistive zones isolated from each other
- H10P: GENERIC PROCESSES OR APPARATUS FOR THE MANUFACTURE OR TREATMENT OF DEVICES COVERED BY CLASS H10
- H01J: ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS (spark-gaps H01T; electric arc lamps H05B31/00; particle accelerators H05H)
- H05B: ELECTRIC HEATING; ELECTRIC LIGHT SOURCES NOT OTHERWISE PROVIDED FOR; CIRCUIT ARRANGEMENTS FOR ELECTRIC LIGHT SOURCES, IN GENERAL

## Abstract

A ceramic heater includes a disc-shaped ceramic substrate that has a wafer placement surface and in which a substrate heater electrode is embedded. The ceramic heater includes a step portion and a step heater electrode. The step portion is annular and extends along an outer periphery of the ceramic substrate to surround the wafer placement surface. The step portion is higher than the wafer placement surface. The step heater electrode is embedded in the step portion. Electric power is supplied to the step heater electrode independently of the substrate heater electrode.

## Claims

### Claim 1

A ceramic heater including a disc-shaped ceramic substrate that has a wafer placement surface and in which a substrate heater electrode is embedded, the ceramic heater comprising:
a step portion that is annular and extends along a outer periphery of the ceramic substrate to surround the wafer placement surface, the step portion being higher than the wafer placement surface; and
a step heater electrode that is embedded in the step portion and to which electric power is supplied independently of the substrate heater electrode.

### Claim 2 (depends on 1)

The ceramic heater according to claim 1,
wherein the step heater electrode includes a plurality of step heater zone electrodes disposed one in each of a plurality of zones into which the step portion is divided in a circumferential direction, and
electric power is independently supplied to each of the step heater zone electrodes.

### Claim 3 (depends on 2)

The ceramic heater according to claim 2,
wherein the step portion has a dividing groove disposed between the zones.

### Claim 4 (depends on 1)

The ceramic heater according to claim 1,
wherein the step portion has an annular groove in a region outside the step heater electrode.

### Claim 5 (depends on 1)

The ceramic heater according to claim 1,
wherein the ceramic substrate is made of aluminum nitride.

### Claim 6 (depends on 1)

The ceramic heater according to claim 1, further comprising:
an RF electrode embedded in the ceramic substrate.

### Claim 7 (depends on 1)

The ceramic heater according to claim 1, further comprising:
an electrostatic electrode embedded in the ceramic substrate.