Wafer-Level Optical Sensor With Selective Transmissive Structure
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current optical detection sensors face challenges in efficiently detecting nearby objects using electromagnetic radiation due to limitations in transmissive structures and alignment of emitter and sensor circuits within wafer-level packaging.
Innovation Solution
The development of an optical detection apparatus and method involving a selectively transmissive structure with aligned transmissive and reflective regions of material, encapsulated with adhesive and polymer materials, allowing for precise alignment and detection of electromagnetic radiation within a wafer-level package.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If a conventional optical detection sensor is used, then object detection function is provided, but the alignment precision between emitter and sensor circuits is insufficient
Solution Approach 1:
Alignment marks are formed on the emitter circuit and sensor circuit before the wafer bonding process. These pre-formed alignment marks enable precise alignment to be achieved during the bonding process, resolving the contradiction between alignment precision and detection reliability by preparing alignment features in advance.
Solution Approach 2:
Alignment marks serve as intermediary features that facilitate the alignment process. These marks are formed on both the emitter and sensor circuits and are used as reference points during wafer bonding, enabling precise alignment without requiring complex alignment mechanisms.
2Adaptability or versatility
If wafer level packaging is implemented, then device integration is improved, but manufacturing complexity increases
Solution Approach 1:
The manufacturing process is segmented into distinct stages: forming alignment marks on the emitter circuit, forming alignment marks on the sensor circuit, bonding the circuits together with precise alignment, and finally forming the encapsulant. This segmentation of the manufacturing process reduces overall complexity by making each step manageable and independent.
Solution Approach 2:
The emitter circuit and sensor circuit are merged into a single integrated device through wafer bonding. This combining of previously separate components into one unified package achieves high device integration while the standardized bonding process keeps manufacturing complexity manageable.
3Illumination intensity
If transmissive material regions are added to the package, then electromagnetic radiation transmission is improved, but the package structure becomes more complex
Solution Approach 1:
Transmissive material regions are added only in specific locations where electromagnetic radiation needs to pass through the package. Rather than making the entire package structure complex, the transmissive regions are localized to specific areas, improving radiation transmission while minimizing structural complexity.
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 enables effective detection of nearby objects by transmitting and reflecting electromagnetic radiation, ensuring proper functionality of the sensor and improving the efficiency of the optical detection process within a compact and integrated wafer-level package.
Implementation Method 1
a first region of transmissive material to allow a first portion of the electromagnetic radiation to pass through the first region to an exterior of the optical detection apparatus
Implementation Method 2
The structure is configured to reflect a second portion of the electromagnetic radiation
Implementation Method 3
a sensor configured to detect the second portion of the electromagnetic radiation
Data Source
AI summary
An optical detection sensor functions as a proximity detection sensor that includes an optical system and a selectively transmissive structure. Electromagnetic radiation such as laser light can be emitted through a transmissive portion of the selectively transmissive structure. A reflected beam can be detected to determine the presence of an object. The sensor is formed by encapsulating the transmissive structure in a first encapsulant body and encapsulating the optical system in a second encapsulant body. The first and second encapsulant bodies are then joined together. In a wafer scale assembling the structure resulting from the joined encapsulant bodies is diced to form optical detection sensors.