Laser-Marked SAW Package Structure for Ultra-Thin Devices
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
There is a need for smaller and thinner packaged surface acoustic wave devices to accommodate increasing demands in semiconductor markets, particularly for applications requiring surface acoustic wave device package heights of 200 microns or less.
Innovation Solution
The development of packaged surface acoustic wave devices with a photosensitive buffer coat layer and direct laser marking on the piezoelectric substrate, which reduces the package height by eliminating post structures and marking films, while maintaining electrical performance and structural integrity.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Length of moving object
If traditional packaging structures with post structures and marking films are used, then structural integrity and identification are ensured, but package height increases
Solution Approach 1:
The patent removes post structures and separate marking films from the packaging design. Instead, the cavity wall directly provides structural support and the piezoelectric substrate itself carries the marking, eliminating unnecessary components that increase height while maintaining structural integrity and identification functions
Solution Approach 2:
The patent combines multiple functions into fewer elements: the cavity wall serves both as structural support and as the surface for forming conductive structures, eliminating the need for separate post structures. The marking is integrated directly into the piezoelectric substrate rather than being a separate film layer, reducing overall package height
2Ease of manufacture
If traditional packaging structures with multiple layers are used, then protection and functionality are ensured, but manufacturing complexity increases
Solution Approach 1:
The patent eliminates several manufacturing steps by removing post structures that require separate formation and attachment processes. The direct formation of conductive structures on the cavity wall and integration of marking into the substrate reduces the number of processing steps and simplifies manufacturing
Solution Approach 2:
The marking is formed directly on the piezoelectric substrate during the packaging process rather than as a separate post-assembly step. The cavity structure is formed to directly support conductive structures without requiring preliminary post structure fabrication, streamlining the manufacturing sequence
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 solution achieves a package height of less than 220 microns, meeting size and cost reduction specifications, and simplifies the manufacturing process by reducing processing steps, thus enabling more efficient and cost-effective production of surface acoustic wave filters for radio frequency applications.
Implementation Method 1
a photosensitive buffer coat layer over the conductive structure
Implementation Method 2
direct laser marking on the piezoelectric substrate
Data Source
AI summary
Methods for making laser-marked packaged surface acoustic wave devices are provided. The method may include directly marking a surface of a piezoelectric substrate, where the opposite surface of the piezoelectric substrate includes a package structure encapsulating a surface acoustic wave device. The method may include exposing the surface of the piezoelectric substrate to light from a deep ultraviolet laser. By using a wavelength readily absorbed by the piezoelectric substrate, a relatively shallow marking may be made in the piezoelectric substrate. The markings may extend less than 1 micrometer into the piezoelectric substrate, and do not affect the structural integrity of the piezoelectric substrate or the operation of the packaged surface acoustic wave device.