Bipolar Electrostatic Chuck Heater for Uniform Wafer Deposition

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Ceramic heaters used in CVD and PVD processes suffer from gas flow vortexes that deteriorate deposition uniformity at the wafer edge, leading to reliability issues.

Innovation Solution

An electrostatic chuck heater with a bipolar structure featuring an internal and external electrode, each capable of selectively performing RF grounding or electrostatic chuck functions, and a bipolar function selector to adapt these functions based on semiconductor process modes, along with a manufacturing method involving ceramic powder sintering and electrode integration.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Stability of the object's composition

If a pocket structure is formed on the ceramic heater to support the wafer, then the wafer can be stably mounted, but gas flow vortexes are generated between the heater upper surface and wafer edge, deteriorating deposition uniformity

Engineering Contradiction:

Improvewafer mounting stabilityVSAvoiddeposition uniformity

Core Design Contradiction:

Stability of the object's compositionVSManufacturing precision

Solution Approach 1:

The invention extracts and removes the problematic pocket structure from the ceramic heater design. By eliminating the recessed pocket that caused gas flow vortexes, the heater surface becomes flat, allowing gas to flow uniformly across the wafer surface without creating eddies or dead zones that would compromise deposition uniformity at the wafer edges.

Inventive Principle:

Principle #2Taking out (Extraction)

Solution Approach 2:

The invention introduces a separate electrostatic chuck mechanism with electrodes positioned close to the wafer surface (within 0.1-10mm distance) to provide localized electrostatic attraction. This allows the main heater surface to remain flat for uniform gas flow, while the electrostatic field provides the necessary holding force in a localized region near the wafer, resolving the conflict between stable mounting and uniform deposition.

Inventive Principle:

Principle #3Local quality

2Temperature

If a ceramic heater is used for precise temperature control, then heating precision is improved, but the pocket structure causes gas flow issues that reduce deposition quality

Engineering Contradiction:

Improvetemperature control precisionVSAvoiddeposition uniformity

Core Design Contradiction:

TemperatureVSManufacturing precision

Solution Approach 1:

The invention merges the heating function and electrostatic chucking function into a single integrated device. The ceramic heater maintains its precise temperature control capability while adding electrostatic electrodes that can independently hold the wafer. This combination allows the heater surface to be flat (eliminating gas flow problems) while the electrostatic field provides the holding force, thus maintaining both temperature precision and deposition uniformity.

Inventive Principle:

Principle #5Merging (Combining)

Solution Approach 2:

The ceramic heater is transformed into a multi-functional device that simultaneously performs heating and electrostatic chucking. By integrating electrodes into the ceramic heater structure, the device can maintain precise temperature control while also providing stable wafer holding through electrostatic forces, eliminating the need for a separate pocket structure and resolving the deposition uniformity issue.

Inventive Principle:

Principle #6Universality (Multi-functionality)

3Manufacturing precision

If the heater surface is made flat to improve gas flow, then deposition uniformity is improved, but wafer mounting stability may be compromised

Engineering Contradiction:

Improvedeposition uniformityVSAvoidwafer mounting stability

Core Design Contradiction:

Manufacturing precisionVSStability of the object's composition

Solution Approach 1:

The invention replaces the mechanical pocket-based holding system with an electrostatic field-based holding system. Instead of relying on a recessed pocket structure to physically hold the wafer, the system uses electrostatic attraction between charged electrodes and the wafer surface. This allows the heater surface to remain completely flat for optimal gas flow, while the electrostatic field provides stable wafer mounting without mechanical interference.

Inventive Principle:

Principle #28Mechanics substitution (Replace mechanical system)

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

Improves temperature and deposition uniformity on the wafer surface by stabilizing the gas flow and enhancing contact between the wafer and the heater, thereby improving thermal conductivity and deposition uniformity.

Implementation Method 1

a heating element 13 for generating thermal energy for heating the substrate

Methodology Applied

Scientific EffectJoule heating: Joule Heating

Implementation Method 2

an electrostatic chuck heater having a bipolar structure featuring an internal and external electrode, each capable of selectively performing RF grounding or electrostatic chuck functions

Methodology Applied

Scientific EffectElectrostatic force: Electrostatics

Data Source

PatentUS12538749B2Electrostatic chuck heater and manufacturing method therefor

Publication Date: 2026.01.27 MICOCERAMICS LTD

AI summary

The present invention relates to an electrostatic chuck heater having a bipolar structure, the electrostatic chuck heater comprising: a heater body having an internal electrode and an external electrode for selectively performing any one of an RF grounding function and an electrostatic chuck function according to a semiconductor process mode; and a heater support mounted below the heater body so as to support the heater body.