Electrostatic Chuck Protrusions Using Hydrogen-Free Amorphous Carbon
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing electrostatic chucks (ESCs) in semiconductor manufacturing suffer from protrusions that are prone to fall off at high temperatures due to poor high-temperature resistance and generate particles that attach to wafers, impacting the manufacturing process.
Innovation Solution
The ESC features protrusions made of hydrogen-free amorphous carbon with resistivity ranging from 10−4 Ω·cm to 10^9 Ω·cm, supported by an adhesive layer of metals like titanium or chromium, which are deposited using carbon plasma and a magnetic field to ensure high hardness, wear resistance, and conductivity, preventing particle attachment and maintaining stability up to 500°C.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Object-generated harmful factors
If protrusions are formed on the ESC surface to reduce particle attachment, then particle generation is reduced, but the protrusions are prone to fall off due to poor high-temperature resistance
Solution Approach 1:
The invention uses hydrogen-free amorphous carbon as the protrusion material, which combines high hardness, wear resistance, and high-temperature stability. This composite material structure maintains protrusion integrity at high temperatures while continuing to reduce particle generation during wafer processing.
Solution Approach 2:
The invention controls the resistivity of hydrogen-free amorphous carbon within a specific range (10^-4 to 10^9 Ω·cm) to optimize both the electrical functionality and thermal stability of the protrusions. By adjusting material parameters, the protrusions maintain stability at high temperatures while preserving their electrostatic function.
2Object-generated harmful factors
If existing protrusions are used, then particle attachment is reduced, but they cannot withstand high-temperature environments
Solution Approach 1:
Hydrogen-free amorphous carbon provides a composite material solution that simultaneously delivers low particle attachment and high-temperature resistance. The unique atomic structure of this material prevents thermal degradation while maintaining surface properties that minimize particle generation.
Solution Approach 2:
The invention replaces traditional protrusion materials with hydrogen-free amorphous carbon that can withstand high temperatures, effectively creating a durable, non-disposable solution that maintains performance throughout the ESC's service life in high-temperature semiconductor processing environments.
3Force
If close contact between wafer and ESC is maintained, then electrostatic adsorption is effective, but friction generates particles
Solution Approach 1:
The invention segments the contact surface by creating protrusions that distribute the wafer-ESC contact at discrete points rather than continuous contact. This segmentation maintains sufficient electrostatic adsorption force while minimizing the total friction area, thereby reducing particle generation.
Solution Approach 2:
The protrusions are strategically positioned and sized to create localized contact zones that concentrate electrostatic forces where needed while leaving non-contact areas that prevent friction-induced particle generation. The local geometry is optimized to balance adsorption and particle reduction.
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
The solution effectively prevents particle generation and attachment, ensuring high-temperature stability and conductivity, reducing the risk of protrusions falling off and improving the semiconductor manufacturing process by maintaining particle-free wafer surfaces.
Implementation Method 1
a carbon plasma is generated by using a graphite target, and a hydrogen-free amorphous carbon layer is deposited over the support surface
Implementation Method 2
the carbon plasma is filtered and/or focused using a magnetic field
Implementation Method 3
The adhesive layer includes a plurality of adhesive parts having the same number as the number of the protrusions. Each of the adhesive parts is placed between the support surface and a corresponding one of the protrusions
Implementation Method 4
an electrostatic chuck (ESC) uses electrostatic adsorption to fix a to-be-processed workpiece, for example, a wafer
Data Source
AI summary
The present disclosure provides an electrostatic chuck (ESC) and a method for manufacturing the plurality of protrusions of the ESC. The electrostatic chuck includes a support surface for carrying a workpiece and the plurality of protrusions distributed at intervals on the support surface. The protrusions are formed by a hydrogen-free amorphous carbon with a resistivity ranging from 10−4 Ω·cm˜109Ω·cm. For the ESC provided by the present disclosure, the protrusions are formed by the hydrogen-free amorphous carbon and have a high hardness and a good wear resistance, which may effectively prevent a generation of particles. As such, the negative impact of the particles on the semiconductor process may be avoided, and the hydrogen does not dissociate in a high-temperature environment. Thereby, a problem that the protrusions may easily fall off and may not be suitable in the high-temperature environment (above 250° C.) may be solved.