Semiconductor Cavity Spacers for RF Antenna Integration
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The integration of radio frequency (RF) devices into semiconductor substrates is hindered by the high dielectric constant of silicon, which affects antenna performance, and the conventional method of forming cavities requires precise alignment and assembly of multiple substrates, making it difficult and costly.
Innovation Solution
A semiconductor substrate with a cavity formed by etching trenches and filling them with dielectric material, where spacers extend from the bottom to the top surface, reducing the need for a second substrate to enclose the cavity and improving alignment precision.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a cavity is formed in one substrate and a second substrate is attached to enclose it, then the cavity can house RF elements, but the alignment and assembly become difficult and costly
Solution Approach 1:
The patent merges the cavity formation and enclosure functions into a single substrate by etching cavities that extend through or into the substrate and using spacers formed from the substrate material itself to provide mechanical support and enclosure, eliminating the need for a separate second substrate and simplifying the manufacturing process
Solution Approach 2:
The substrate is segmented into regions including cavity portions and spacer portions, where the spacer material is separated from the cavity space but remains mechanically connected to the substrate, allowing the cavity to be enclosed without requiring a separate enclosing substrate
2Device complexity
If an antenna is located proximate to silicon substrate, then integration is achieved, but performance is adversely affected due to high dielectric constant
Solution Approach 1:
The patent applies local quality by creating regions with different dielectric properties within the substrate - specifically, cavities with air or low-dielectric-constant material filling, surrounded by spacer structures, allowing the antenna to be integrated into the substrate while locally modifying the dielectric environment to improve performance
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 allows for the formation of high-performance RF systems with integrated antennae and IC chips on a single substrate, reducing manufacturing complexity and cost while maintaining high data transmission rates and low power consumption.
Implementation Method 1
in view of the relatively large dielectric constant of silicon (k ̃11.9), locating an antenna for such devices proximate to such a high dielectric constant material can adversely affect performance. Improved performance can be achieved by locating antennae proximate to an air gap (or cavity).
Data Source
AI summary
An electronic package apparatus is formed from a semiconductor substrate having a cavity formed therein. The cavity has a top surface, a bottom surface and a sidewall surface, and a spacer extending from the bottom surface to the top surface. The spacer is formed from a dielectric material and has at least one lateral dimension less than 0.1 cm.