Electron Microscope Retarding Voltage Control for Insulating Samples
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing electron microscope technologies face challenges in applying a retarding voltage to semiconductor samples with insulating films, leading to electrical insulation and sample damage, while maintaining high-resolution imaging and preventing electrification.
Innovation Solution
A scanning electron microscope with an electrostatic-chuck mechanism and a contact terminal that applies a negative voltage to the sample through a contact pin, ensuring electrical conduction and stabilizing the sample's electric potential despite insulating films, using a retarding voltage applying circuit that adjusts potential differences between internal electrodes to establish and maintain electrical conduction.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If a high-accelerating-energy electron beam is used for high-resolution imaging, then image resolution is improved, but sample damage and electrification occur
Solution Approach 1:
The patent applies a negative voltage to the sample stage before electron beam irradiation to pre-establish a decelerating electric field. This preliminary action reduces the kinetic energy of electrons before they reach the sample, preventing sample damage and electrification while maintaining high-resolution imaging capability through the objective lens
Solution Approach 2:
The patent dynamically adjusts the accelerating voltage of the electron beam and the negative voltage applied to the sample stage during observation. By making these voltage parameters adjustable and changeable during the process, the system can optimize between resolution and sample protection based on specific observation needs
2Object-affected harmful factors
If a negative voltage is applied to the sample for retarding the electron beam, then sample protection is improved, but electrical insulation occurs due to insulating films
Solution Approach 1:
The patent divides the voltage application into separate components: the electron beam accelerating voltage and the sample stage negative voltage. This segmentation allows independent control of each voltage parameter, enabling the retarding field to be applied through the stage while maintaining proper electrical conduction paths
Solution Approach 2:
The patent uses the sample stage as an intermediary component to apply the negative voltage. Instead of directly applying voltage to the sample (which would be blocked by insulating films), the stage acts as a mediator that creates a decelerating electric field in the space between the objective lens and the sample, bypassing the insulating film barrier
3Reliability
If conventional grounding methods are used with insulating films, then electrical conduction is difficult to establish, but mechanical breaking or chemical clarification increases device complexity
Solution Approach 1:
The patent replaces mechanical grounding methods (such as breaking through insulating films with pins or mechanical contact) with an electrical field-based approach. By applying a negative voltage to the stage, a decelerating electric field is created that does not require direct mechanical contact or breakdown of insulating films, thereby simplifying the grounding mechanism
Solution Approach 2:
The patent changes the electrical parameters of the system by applying a controllable negative voltage to the stage. This parameter change allows the system to achieve both sample protection and electrical conduction by adjusting the voltage magnitude and polarity, eliminating the need for complex mechanical or chemical grounding procedures
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
Enables stable application of retarding voltage to semiconductor samples with insulating films, preventing sample damage and image distortion, while ensuring high-resolution imaging and smooth sample transportation.
Implementation Method 1
an electrostatic-chuck mechanism for providing a potential difference among a plurality of its internal electrodes, and thereby generating an adsorption force to be exerted onto the sample
Implementation Method 2
a negative-voltage applying power-supply for applying a negative voltage to the sample, and thereby forming a decelerating electric field to be exerted onto the electron beam
Implementation Method 3
a contact terminal which is so configured as to come into contact with the sample when the sample is deployed on the sample-supporting stage
Data Source
AI summary
It is an object of the present invention to provide an electron microscope for properly applying a retarding voltage to a sample which is brought into electrical conduction.In order to accomplish the above-described object, the following electron microscope is proposed: The electron microscope including a negative-voltage applying power-supply for applying the negative voltage to the sample, and thereby forming a decelerating electric field to be exerted onto the electron beam, an electrostatic-chuck mechanism for providing a potential difference among a plurality of its internal electrodes, and thereby generating an adsorption force to be exerted onto the sample, and a contact terminal which is so configured as to come into contact with the sample when the sample is deployed on a sample-supporting stage, the electrostatic-chuck mechanism causes the potential difference to occur among the internal electrodes in the state where the contact terminal comes into contact with the sample, the negative-voltage applying power-supply being operated to apply the negative voltage to the contact terminal after the potential difference has been caused to occur.