Cryopump Temperature Control for Idle-Mode Power Reduction
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Cryopumps used in semiconductor circuit manufacturing and ion implantation processes face challenges in achieving high performance while minimizing power consumption, particularly in managing gas molecule evacuation during varying operational modes.
Innovation Solution
A cryopump system with a cryopanel and refrigerator controlled by a control unit that adjusts cooling temperatures based on operation modes, allowing higher temperatures during idle modes to reduce power consumption by lowering pumping speed when high-speed pumping is not necessary.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If the cryopanel is cooled to a low temperature to maintain high pumping speed, then gas molecule capture performance is improved, but power consumption increases
Solution Approach 1:
The cryopump system dynamically adjusts the cooling temperature of the cryopanel based on operational requirements. During idle periods, the temperature is raised to reduce refrigerator workload and power consumption. During active pumping periods, the temperature is lowered to maximize pumping speed. This dynamic temperature adjustment resolves the contradiction between maintaining high pumping performance and minimizing energy consumption.
Solution Approach 2:
The system changes the operating parameter (temperature) of the cryopanel according to different operational states. By varying the temperature parameter between low (for high pumping speed) and higher (for energy saving), the system optimizes the balance between productivity and energy consumption, directly addressing the technical contradiction.
2Productivity
If the cooling temperature is maintained at a low level continuously, then gas molecule evacuation efficiency is improved, but energy waste occurs during idle periods
Solution Approach 1:
The cryopump operates with periodic temperature adjustments corresponding to periodic operational demands. The refrigerator cycles between high-power cooling modes during active pumping and reduced-power modes during idle periods. This periodic action pattern ensures high evacuation efficiency when needed while preventing continuous energy waste during idle times.
Solution Approach 2:
The control system anticipates operational changes and adjusts the cooling temperature in advance. When transitioning from idle to active mode, the system begins cooling the cryopanel before full pumping demand is required, ensuring optimal temperature is reached when pumping begins. This preliminary action maintains evacuation efficiency while minimizing the duration of high-power consumption.
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 reduces power consumption by optimizing cooling temperatures according to operational modes, ensuring efficient gas molecule capture and evacuation while minimizing energy usage during periods of reduced thermal load.
Implementation Method 1
A cryopump is a vacuum pump which captures gas molecules on a cryopanel cooled to an extremely low temperature by condensation or adsorption
Implementation Method 2
A cryopump is a vacuum pump which captures gas molecules on a cryopanel cooled to an extremely low temperature by condensation or adsorption
Implementation Method 3
a refrigerator which cools the cryopanel
Data Source
AI summary
A cryopump includes a refrigerator which cools a cryopanel and a controller which receives a control signal representing an operation mode from a beam irradiating apparatus and controls the refrigerator based on the control signal. The operation mode includes an irradiation mode for irradiating a beam to a target and an idle mode for diverting the beam from the target or keeping the beam with a level weaker than that of the irradiation mode. The controller controls the refrigerator such that the cryopanel is cooled in both the irradiation mode and the idle mode to a cooling temperature at which gas molecules are held and allows the cooling temperature in at least a part of the period of the idle mode to be higher than that of the irradiation mode.