Transfer Head Array Shielding Layer for Electrostatic Interference
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Transfer head arrays face interference from superfluous electric fields during the micro device transfer process, leading to misalignment or unwanted gripping of micro devices due to external electronic devices, which disrupt the precise operation of electrostatic transfer heads.
Innovation Solution
Incorporation of a shielding layer made of conductive materials like aluminum, titanium, or copper, electrically connected to an AC or DC power source, positioned to overlap with areas outside the picking surface to block interfering electric fields and maintain the integrity of the electrostatic force used for gripping micro devices.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Force
If transfer heads use electrostatic force to grip micro devices, then gripping capability is improved, but susceptibility to external electric field interference worsens
Solution Approach 1:
A shielding layer made of conductive material is introduced as an intermediary between the external environment and the transfer head array. This shielding layer blocks external electric fields from directly interacting with the electrostatic chuck, while allowing the transfer head to maintain its electrostatic gripping function. The shielding layer acts as a mediator that filters harmful external fields while permitting the controlled electrostatic field necessary for gripping to operate effectively.
Solution Approach 2:
The patent creates an electrically shielded environment around the transfer head array by enclosing it with a conductive shielding layer connected to ground. This creates an 'inert' electromagnetic environment that isolates the sensitive electrostatic gripping mechanism from external electric field disturbances, similar to how an inert gas atmosphere protects chemical reactions from unwanted interactions.
2Object-affected harmful factors
If shielding layer is added to block external electric fields, then resistance to interference is improved, but device complexity worsens
Solution Approach 1:
The shielding layer is implemented as a thin conductive film or shell that can be integrated into the existing transfer head array structure. This thin-film approach provides effective electric field shielding while minimizing the added structural complexity and maintaining a compact design. The shielding layer can be deposited as a thin coating on the base substrate or transfer head components.
Solution Approach 2:
The patent modifies the electrical parameters of the system by introducing a grounded conductive layer, which changes the electric field distribution without fundamentally altering the mechanical or operational parameters of the transfer head array. This parameter-based solution (adding a conductive layer with specific electrical properties) provides shielding while keeping the overall device structure relatively simple.
3Adaptability or versatility
If transfer head array operates in presence of external electronic devices, then operational flexibility is improved, but positioning precision worsens due to unwanted electrostatic forces
Solution Approach 1:
The shielding layer serves as a protective intermediary that allows the transfer head array to operate in environments with external electronic devices. It blocks unwanted electrostatic forces from these external devices while permitting the controlled electrostatic field from the transfer head to grip and position micro devices with high precision. This intermediary protection enables both operational flexibility and positioning precision to coexist.
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 shielding layer effectively prevents external electric fields from interfering with the transfer heads, ensuring accurate gripping and positioning of micro devices by isolating the picking surface from unwanted electrostatic forces, thereby enhancing the reliability of the transfer process.
Implementation Method 1
The shielding layer is disposed in the interlayer isolation layer... effectively prevents external electric fields from interfering with the transfer heads... isolating the picking surface from unwanted electrostatic forces
Implementation Method 2
The transfer head creates grip force on the micro devices, such as electrostatics force, vacuum force, adhesion force, or mechanical force
Data Source
AI summary
A transfer head array includes a base substrate, an interlayer isolation layer, plural transfer heads, and at least one shielding layer. The interlayer isolation layer is disposed on the base substrate, and the interlayer isolation layer has a flat top surface facing away from the base substrate. The transfer heads are arranged on the interlayer isolation layer. The shielding layer is disposed in the interlayer isolation layer.