Load Lock Wafer Conditioning for Faster Particle Beam Inspection
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The presence of pattern defects and uninvited particles on semiconductor wafers during IC chip fabrication reduces yield, and conventional particle beam inspection systems face challenges with wafer temperature stabilization, leading to reduced throughput due to the need for prolonged waiting times for temperature stabilization before inspection.
Innovation Solution
An improved load lock system with a conditioning plate that adjusts the temperature of the wafer before inspection, using a heat transfer element and gas vent to stabilize the wafer temperature close to that of the inspection stage, allowing simultaneous conditioning and inspection of subsequent wafers.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If wafer temperature stabilization is performed before inspection, then inspection accuracy is improved, but system throughput deteriorates due to prolonged waiting times
Solution Approach 1:
The load lock system performs preliminary temperature conditioning of the wafer before it enters the inspection chamber. The conditioning plate adjusts the wafer temperature to match the inspection stage temperature in advance, so that when the wafer is transferred for inspection, no additional temperature stabilization time is needed, thereby eliminating the throughput bottleneck while maintaining inspection accuracy
Solution Approach 2:
The load lock system acts as an intermediary chamber between the wafer loading area and the inspection chamber. It houses a conditioning plate that independently adjusts wafer temperature before transfer, serving as a buffer zone that decouples the temperature conditioning process from the inspection process, allowing both to occur in parallel without interfering with each other
2Temperature
If wafer temperature is adjusted using conventional methods, then temperature stabilization is achieved, but inspection throughput deteriorates due to sequential processing requirements
Solution Approach 1:
The system segments the wafer processing into distinct functional zones: a load lock chamber for temperature conditioning and a separate inspection chamber for pattern inspection. This spatial segmentation allows temperature adjustment and inspection to occur simultaneously in different locations, transforming a sequential process into a parallel one and dramatically improving throughput
Solution Approach 2:
The load lock chamber serves as an intermediary processing stage that handles temperature conditioning independently. By placing the conditioning plate in this intermediate zone rather than in the inspection chamber itself, the system allows temperature adjustment and inspection to proceed concurrently, eliminating the need for sequential processing
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 approach enhances throughput by minimizing wait times for temperature stabilization, enabling faster and more accurate inspection of wafers, thus improving overall system efficiency and yield.
Implementation Method 1
enabling a first heat transfer element in a first conditioning plate to adjust a temperature of the first conditioning plate for transferring heat through the gas to the wafer
Implementation Method 2
providing a gas between the first conditioning plate and the wafer
Data Source
AI summary
An improved particle beam inspection apparatus, and more particularly, a particle beam inspection apparatus including an improved load lock unit is disclosed. An improved load lock system may comprise a plurality of supporting structures configured to support a wafer and a conditioning plate including a heat transfer element configured to adjust a temperature of the wafer. The load lock system may further comprise a gas vent configured to provide a gas between the conditioning plate and the wafer and a controller configured to assist with the control of the heat transfer element.