Embedded ESC Cathode Assembly With Isolated RF and DC Inputs
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing electrostatic chuck (ESC) structures in semiconductor manufacturing suffer from significant current leakage due to the combined input of RF and DC voltage, leading to uncontrollable chucking force, wafer damage, increased costs, and reduced efficiency.
Innovation Solution
The implementation of an electrostatic chuck with a DC input line electrically isolated from the RF feed, utilizing a ceramic insert with an embedded electrode and a facility plate with an insulating collar to prevent electrical interaction between DC and RF components, along with a dual-zone gas delivery system for enhanced thermal control.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Device complexity
If RF and DC voltage are provided through a single input to the ESC, then the device structure is simplified, but current leakage increases
Solution Approach 1:
The single input structure is segmented into separate RF and DC voltage inputs. The facility plate includes distinct RF feed lines and DC input connectors, physically separating the transmission paths for RF and DC signals to prevent current leakage while maintaining functional independence of each voltage source
Solution Approach 2:
An electrically insulating collar is introduced as an intermediary component between the DC input connector and the facility plate body. This collar acts as a mediator that electrically isolates the DC voltage path from the RF feed lines, preventing current leakage while allowing both signals to coexist in the same structural environment
2Adaptability or versatility
If DC current flows through the RF feed line, then the feed line structure is utilized efficiently, but uncontrollable chucking force is generated
Solution Approach 1:
The electrical input paths are segmented into dedicated DC input connectors and RF feed lines. The DC voltage is delivered through separate connectors that bypass the RF feed lines, ensuring that DC current does not flow through the RF transmission paths and preventing interference with the electrostatic chucking force control
3Device complexity
If RF and DC inputs are electrically connected, then the ESC structure is simplified, but wafer damage occurs
Solution Approach 1:
The electrically insulating collar serves as a mediator that physically and electrically separates the DC input connector from the RF feed lines and facility plate body. This intermediary component prevents harmful electrical interactions between DC and RF inputs that could otherwise cause wafer damage, while maintaining a relatively simple overall ESC structure
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
Reduces current leakage, maintains consistent chucking force, minimizes wafer damage, and enhances the efficiency and cost-effectiveness of semiconductor processing tools by isolating DC and RF inputs.
Implementation Method 1
The ESC provides an electrostatic force that attracts the wafer to the chuck in order to prevent movement of the wafer during processing.
Implementation Method 2
a pin of the DC input connector is electrically isolated from the RF feed line
Data Source
AI summary
Embodiments disclosed herein include an apparatus that includes an electrostatic chuck (ESC). The electrostatic chuck may include a first body that is electrically conductive, and a ceramic insert on the first body with an electrode embedded within the ceramic insert. In an embodiment, the apparatus may further include a facility plate that is coupled to the ESC. The facility plate may include a second body that is electrically conductive with a hole through the second body. In an embodiment, a DC input connector is provided through the hole, and an RF feed line is coupled to the second body. In an embodiment, a pin of the DC input connector is electrically isolated from the RF feed line.