Via Hole Etching for Semiconductor Packages
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The formation of defective via holes in silicon substrates during the etching process for semiconductor devices leads to reliability issues, such as shape variations and stress concentration, which can cause damage and deteriorate the via plug's performance.
Innovation Solution
A method involving a two-step etching process to form via holes, first in a straight shape and then in a taper shape, using a combination of anisotropic and isotropic dry etching or dry and wet etching techniques, along with forming concave portions for improved semiconductor device mounting.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If a via hole is formed by dry etching with a mask pattern, then the via hole can be formed to penetrate through the silicon substrate, but defective shapes and stress concentration occur at the opening portion
Solution Approach 1:
The etching process is divided into two distinct steps: a first etching step to form the via hole through the silicon substrate, and a second etching step to form a recess portion at the opening. This segmentation allows each step to optimize for its specific function, preventing shape defects and stress concentration that would occur in a single etching process.
Solution Approach 2:
The via hole structure is given different local geometries: the main body of the via hole maintains a cylindrical shape for electrical conductivity, while the opening portion is formed with a recess that reduces stress concentration. This local differentiation of geometry addresses the specific problem at the opening without compromising the overall via hole function.
2Ease of manufacture
If the via hole opening is formed with a mask pattern interface, then etching can be performed, but fine peeling and defective shapes occur at the interface
Solution Approach 1:
The first etching step is performed preliminarily to form the via hole through the substrate before the second etching step creates the recess portion. This preliminary formation of the via hole body allows the opening to be processed separately with optimized conditions, avoiding the mask interface problems that would occur if the opening were formed simultaneously with the via hole.
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 enhances the reliability of the via plug by reducing shape variations and stress concentration, leading to improved electrical connections and increased durability of the semiconductor package.
Implementation Method 1
said first etching step is carried out by anisotropic dry etching
Implementation Method 2
said second etching is carried out by isotropic dry etching
Implementation Method 3
a step of embedding conductive material in the via hole to form a via plug
Data Source
AI summary
A method for manufacturing a package which includes: an etching step of etching a silicon substrate, and forming a via hole penetrating through the silicon substrate; and a step of embedding an electrically conductive material in the via hole, and forming a via plug, characterized in that the etching step includes a first etching step of forming the via hole in a straight shape, and a second etching step of forming the via hole in a taper shape.