Thermally Isolated Heater Plate Blocks for Plasma Processing
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current wafer chucks in plasma processing chambers face challenges in achieving precise thermal uniformity and control, leading to variations in temperature across the wafer surface, which affects the etching rates and precision of semiconductor fabrication.
Innovation Solution
A workpiece carrier with isolated heater plate blocks and a cooling plate, where each heater zone is independently controlled using resistive heaters and temperature sensors, and a cooling system with heat transfer fluid channels to maintain precise temperature control across the wafer surface.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Temperature
If liquid cooling is used to remove plasma power heat from the chuck, then heat removal capability is improved, but temperature uniformity across the wafer surface deteriorates
Solution Approach 1:
The heater plate is divided into multiple thermally isolated blocks, each capable of independent temperature control. This segmentation allows different regions to be heated or cooled independently, compensating for the non-uniform cooling effects and achieving precise temperature uniformity across the wafer surface while maintaining effective heat removal capability.
2Manufacturing precision
If independently controlled heaters are used in multiple zones, then temperature control precision is improved, but device complexity increases
Solution Approach 1:
The heater plate is segmented into multiple thermally isolated blocks with independent heaters and temperature sensors. Each block can be controlled independently through a temperature controller, enabling precise local temperature adjustment without requiring an overly complex distributed control system, as the thermal isolation naturally decouples the control requirements.
3Temperature
If a single uniform temperature is maintained across the chuck, then thermal uniformity is improved, but adaptability to different process conditions deteriorates
Solution Approach 1:
Different zones of the heater plate can be maintained at different temperatures according to specific process requirements. The independently controllable thermal blocks allow the system to adapt to various plasma processing conditions by adjusting local temperatures, while still achieving overall thermal uniformity when needed, providing both thermal control modes.
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 allows for precise thermal management, reducing temperature variations to less than ±0.3°C, enabling more precise control over etching processes and the formation of smaller structures on semiconductor wafers.
Implementation Method 1
each block includes a heater to heat a respective block of the heater plate
Implementation Method 2
the cooling plate defining a cooling channel configured to distribute a heat transfer fluid to transfer heat from the cooling plate
Implementation Method 3
the cooling plate fastened to and thermally coupled to the heater plate
Implementation Method 4
each heater zone is independently controlled using resistive heaters and temperature sensors
Data Source
AI summary
A workpiece carrier is described for a plasma processing chamber that has isolated heater plate blocks. In one example, a plasma processing system has a plasma chamber, a plasma source electrically coupled with a showerhead included within the plasma chamber, a workpiece holder in a processing region of the plasma chamber having a puck to carry a workpiece, wherein the workpiece holder includes a heater plate having a plurality of thermally isolated blocks each thermally coupled to the puck, wherein each block includes a heater to heat a respective block of the heater plate, and wherein the workpiece holder includes a cooling plate fastened to and thermally coupled to the heater plate, the cooling plate defining a cooling channel configured to distribute a heat transfer fluid to transfer heat from the cooling plate, and a temperature controller to independently control each heater.