Plasma Needle Bevel Cleaning for Semiconductor Deposit Removal
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing substrate processing systems face challenges in effectively cleaning deposits from bevel and backside regions of semiconductor substrates, leading to issues like defocusing during lithography and stress in the bevel region due to unwanted film deposition and particle accumulation.
Innovation Solution
A system featuring plasma needles or edge electrodes around the substrate support, which generate plasma using reactive gases and an RF bias to etch and remove deposits, combined with a rotating substrate support for controlled exposure to plasma, ensuring efficient cleaning of the bevel regions.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If conventional substrate processing systems are used, then deposition of film on substrate can be performed, but cleaning of deposits from bevel and backside regions is ineffective
Solution Approach 1:
The substrate support is segmented into multiple independent plasma needles arranged around its perimeter, each capable of generating plasma independently. This segmentation allows targeted cleaning of different regions of the substrate bevel and backside, improving cleaning effectiveness while addressing the harmful effect of deposit accumulation through distributed plasma sources
Solution Approach 2:
A central injector is introduced as an intermediary component that supplies purge gas to the center of the substrate support. This intermediary element helps control plasma exposure by providing gas flow that modulates the plasma-cleaned regions, enhancing the overall cleaning effectiveness while managing the harmful effects of uncontrolled deposition
2Object-generated harmful factors
If plasma cleaning is applied to bevel regions, then deposit removal is improved, but unwanted film deposition and stress may occur
Solution Approach 1:
Different regions of the substrate support are assigned different functions: plasma needles at the perimeter provide aggressive cleaning for heavy deposit removal, while the central injector provides gentler purge gas flow for regions requiring less intense cleaning. This local differentiation allows effective deposit removal while controlling unwanted film deposition and stress by matching cleaning intensity to local needs
Solution Approach 2:
The system applies partial plasma cleaning action through selectively activated plasma needles and controlled purge gas flow. By not applying plasma uniformly across all regions, the system achieves effective deposit removal where needed while avoiding excessive cleaning that could cause unwanted film deposition or stress in other areas
3Manufacturing precision
If multiple plasma needles are arranged around substrate support, then cleaning coverage is improved, but device complexity increases
Solution Approach 1:
The substrate support structure serves multiple functions: it holds the substrate, provides mounting for plasma needles, enables rotation for uniform exposure, and incorporates a central injector for purge gas delivery. This multi-functionality improves cleaning coverage through coordinated plasma and gas flow while avoiding the need for separate dedicated components, thereby managing device complexity
4Manufacturing precision
If substrate support rotates during plasma cleaning, then uniform exposure is achieved, but process time increases
Solution Approach 1:
The substrate support rotates continuously during plasma cleaning to ensure all regions receive uniform plasma exposure. This continuous rotation, combined with continuously active plasma needles and purge gas flow, maintains effective cleaning action throughout the process, achieving uniformity while minimizing idle time that would otherwise extend process duration
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 system provides improved cleaning of edge and bevel regions, reducing unwanted deposition and stress, thereby enhancing product yields and quality by uniformly exposing the bevel regions to plasma for effective etching and deposition control.
Implementation Method 1
The plasma needles are in fluid communication with a gas delivery system and are configured to supply reactive gases from the gas delivery system to a bevel region of the substrate and electrically couple to the electrode of the substrate support and generate plasma around the bevel region of the substrate
Implementation Method 2
each ALD cycle includes precursor dose, purge, RF plasma dose, and purge steps
Implementation Method 3
The edge electrode is in fluid communication with a gas delivery system and the edge electrode is configured to supply reactive gases from the gas delivery system to the volume and receive power to generate plasma within the volume
Data Source
AI summary
A system for performing a bevel cleaning process on a substrate includes a substrate support including an electrode and a plurality of plasma needles arranged around a perimeter of the substrate support. The plasma needles are in fluid communication with a gas delivery system and are configured to supply reactive gases from the gas delivery system to a bevel region of the substrate when the substrate is arranged on the substrate support and electrically couple to the electrode of the substrate support and generate plasma around the bevel region of the substrate.