Benchmark Wafer Circuit Isolation for Antenna Effect Measurements
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The antenna effect during semiconductor device manufacturing causes yield and reliability issues due to charge induction, which existing solutions like antenna diodes can't fully address without interfering with post-manufacture measurements and potentially damaging the device.
Innovation Solution
A benchmark device on a semiconductor wafer with a transistor, diode, and a disconnecting switch that forms a conductive path during manufacturing and isolates the transistor from the diode post-manufacture, allowing for interference-free measurements and preventing damage from focused ion beam processes.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If an antenna diode is connected to the wiring to protect the semiconductor device during manufacture, then the device is protected from antenna effect damage, but the measurements after manufacture are disturbed
Solution Approach 1:
The benchmark device is segmented into distinct functional components: a transistor for measurements, an antenna diode for protection, and a disconnecting switch with fuse element to separate these functions. The disconnecting switch divides the circuit path, allowing the antenna diode to be electrically isolated from the transistor during measurement phases while remaining connected during manufacturing phases.
Solution Approach 2:
The disconnecting switch provides dynamic reconfiguration of the circuit topology. During manufacturing, the switch is in a closed state connecting the antenna diode to protect against antenna effects. After manufacturing, the fuse element opens the switch, dynamically changing the circuit from a protected configuration to a measurement-optimized configuration without requiring physical removal of components.
2Measurement precision
If FIB is used to remove the antenna diode after manufacture, then the measurement interference is eliminated, but undesired damages may occur to the semiconductor device
Solution Approach 1:
The disconnecting switch with fuse element acts as an intermediary mechanism between the antenna diode and the transistor. Instead of using FIB to physically remove the antenna diode, the fuse element provides a controlled electrical disconnection path. This intermediary approach eliminates measurement interference while avoiding the harmful physical intervention of FIB on the semiconductor structure.
Solution Approach 2:
The patent replaces the mechanical/physical removal process (FIB) with an electrical disconnection mechanism (fuse element in the disconnecting switch). The fuse element opens an electrical circuit path through thermal breakdown when exposed to a current pulse, substituting a controlled electrical event for the mechanical sputtering process of FIB, thereby eliminating the risk of structural damage.
3Reliability
If the antenna diode is kept connected to protect during manufacture, then protection is maintained, but the device complexity increases
Solution Approach 1:
The disconnecting switch with fuse element provides multi-functionality: during manufacturing, it connects the antenna diode to provide protection; after manufacturing, it opens to enable accurate measurements. This single component structure serves multiple purposes at different stages, reducing the need for separate protection circuits and measurement circuits, thereby managing device complexity efficiently.
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
Enables accurate post-manufacture measurements by eliminating interference from the antenna diode and preventing unwanted damage to the semiconductor device, ensuring reliable device performance.
Implementation Method 1
The disconnecting switch is configured to form a conductive path between the transistor and the diode at a first stage
Implementation Method 2
to electrically isolate the transistor from the diode at a second stage
Implementation Method 3
The disconnecting switch is configured to electrically disconnect the gate electrode of the transistor from the cathode electrode of the diode in response to a current exceeding a predetermined value through the disconnecting switch
Data Source
AI summary
The present disclosure provides a method of operating a benchmark device embedded on a semiconductor wafer. The method includes applying a first voltage to a first electrode of the benchmark device, and applying a second voltage to a second electrode of the benchmark device. The method further includes electrically isolating a first component of the benchmark device from a second component of the benchmark device through a disconnecting switch connected between the first component and the second component.