Substrate Support Warpage Control via Low Thermal Expansion
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The existing substrate supports in inspection apparatuses can warp due to temperature differences caused by light irradiation mechanisms, leading to uneven heating and warpage, which affects the flatness and stability of the substrate.
Innovation Solution
A substrate support design incorporating a supporting unit with a low thermal expansion material plate member and a transparent member, along with a thermally sprayed insulating film and resistance temperature detector film, which allows controlled temperature distribution and minimizes warpage by managing thermal expansion through controlled light irradiation and coolant flow.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Temperature
If light irradiation mechanism is used to heat the inspection target, then the temperature of the inspection target is increased, but the substrate support warps due to temperature difference between upper surface and bottom surface of the cooling mechanism
Solution Approach 1:
A temperature distribution control unit is introduced as an intermediary component between the light irradiation mechanism and the substrate support. This control unit irradiates light not only to the inspection target but also to the cooling mechanism and substrate support, creating a compensating heat distribution that prevents warpage while maintaining the required temperature increase at the inspection target.
Solution Approach 2:
The light irradiation is made non-uniform across different regions of the substrate support. The temperature distribution control unit selectively irradiates different areas with different intensities, creating localized heating zones that compensate for the temperature gradient caused by the light irradiation mechanism. This ensures uniform temperature distribution and prevents warpage in specific critical areas.
2Manufacturing precision
If light irradiation mechanism heats only a limited area, then the inspection area is concentrated, but high-temperature and low-temperature regions coexist causing warpage of the substrate support
Solution Approach 1:
The temperature distribution control unit changes the spatial distribution parameter of light irradiation. By adjusting the irradiation pattern to cover both the inspection target and surrounding areas of the cooling mechanism, it modifies the temperature field distribution, reducing the temperature gradient between high-temperature and low-temperature regions while maintaining precise temperature control at the inspection target.
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
The design effectively suppresses warpage and maintains the flatness of the substrate by evenly distributing temperature changes across the support surface, ensuring stable placement and inspection of electronic devices.
Implementation Method 1
When the inspection target is heated by the light irradiation mechanism, an upper surface side of the cooling mechanism is heated
Implementation Method 2
The cooling mechanism is a light transmitting member and allows a coolant (refrigerant) capable of transmitting light to flow therethrough
Implementation Method 3
the substrate support may be warped (bent) due to a temperature difference between the upper surface and a bottom surface of the cooling mechanism
Data Source
Figure 1
Figure 2
Figure 3A~3B
AI summary
A substrate support includes a supporting unit and a light irradiation mechanism. The supporting unit includes a plate member on which an inspection target is placed and a transparent member. The light irradiation mechanism is configured to irradiate light to increase a temperature of the inspection target. Each of the plate member and the transparent member is made of a low thermal expansion material having a linear expansion coefficient of 1.0×10-6/K or less.