Electrostatic Chuck Radial Heater Zones for Temperature Uniformity

Solution Overview

Problem

Substrate processing in chambers often results in non-uniform processing rates and temperature variations across the substrate surface due to uneven gas distribution, plasma species distribution, and non-uniform heat loads, leading to undesirable processing outcomes for semiconductors and displays.

Innovation Solution

An electrostatic chuck with a ceramic puck featuring a substrate receiving surface with mesas, embedded electrodes, and radially spaced heater coils, along with heat transfer gas conduits, is used to maintain uniform processing by controlling temperature and gas distribution across the substrate surface.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Device complexity

If a single heating zone is used in the electrostatic chuck, then the structure is simple, but the temperature distribution across the substrate surface becomes non-uniform

Engineering Contradiction:

Improveheater structureVSAvoidtemperature uniformity

Core Design Contradiction:

Device complexityVSTemperature

Solution Approach 1:

The heating system is divided into multiple independent heating zones (first heating zone, second heating zone, third heating zone) with separate heater coils, allowing independent temperature control of different regions to achieve uniform temperature distribution across the substrate surface

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

Different regions of the electrostatic chuck are assigned different heating characteristics through localized heater coils in different zones, enabling tailored temperature control for central and peripheral regions to compensate for non-uniform heat loads and achieve overall temperature uniformity

Inventive Principle:

Principle #3Local quality

2Manufacturing precision

If uniform gas distribution is provided across the substrate, then the processing becomes uniform, but the device complexity increases due to multiple gas conduits and ports

Engineering Contradiction:

Improveprocessing uniformityVSAvoidgas distribution system

Core Design Contradiction:

Manufacturing precisionVSDevice complexity

Solution Approach 1:

The gas distribution system is segmented into multiple independent gas conduits (first gas conduit, second gas conduit) with separate ports, allowing independent control of gas flow to different regions of the substrate to achieve uniform gas distribution and processing uniformity

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

Different regions of the substrate receive gas through dedicated conduits and ports positioned to deliver uniform gas distribution across central and peripheral regions, enabling localized gas flow control to compensate for non-uniform processing conditions

Inventive Principle:

Principle #3Local quality

Applied Scientific Principles

This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.

Function Achieved in This Case

This solution ensures more uniform processing rates and characteristics across the substrate surface by independently controlling temperatures and gas distribution, counteracting variability in gas species and heat loads, thereby enhancing the fabrication of electronic devices.

Implementation Method 1

An electrostatic chuck for receiving a substrate in a substrate processing chamber comprises a ceramic puck having a substrate receiving surface having a plurality of spaced apart mesas, an opposing backside surface, and central and peripheral portions. A plurality of heat transfer gas conduits traverse the ceramic puck and terminate in ports on the substrate receiving surface to provide heat transfer gas to the substrate receiving surface. An electrode is embedded in the ceramic puck to generate an electrostatic force to retain a substrate placed on the substrate receiving surface.

Methodology Applied

Scientific EffectElectrostatic force: Electrostatics

Implementation Method 2

A plurality of heater coils are also embedded in the ceramic puck, the heaters being radially spaced apart and concentric to one another.

Methodology Applied

Scientific EffectJoule heating: Joule Heating

Implementation Method 3

A plurality of heat transfer gas conduits traverse the ceramic puck and terminate in ports on the substrate receiving surface to provide heat transfer gas to the substrate receiving surface.

Methodology Applied

Scientific EffectThermal conduction: Conduction (thermal)

Data Source

PatentUS8663391B2Electrostatic chuck having a plurality of heater coils

Publication Date: 2014.03.04 APPLIED MATERIALS INC

AI summary

An electrostatic chuck for receiving a substrate in a substrate processing chamber comprises a ceramic puck having a substrate receiving surface having a plurality of spaced apart mesas, an opposing backside surface, and central and peripheral portions. A plurality of heat transfer gas conduits traverse the ceramic puck and terminate in ports on the substrate receiving surface to provide heat transfer gas to the substrate receiving surface. An electrode is embedded in the ceramic puck to generate an electrostatic force to retain a substrate placed on the substrate receiving surface. A plurality of heater coils are also embedded in the ceramic puck, the heaters being radially spaced apart and concentric to one another.