Semi-Automatic Multiplexing System for Semiconductor Wafer Testing
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing semiconductor wafer testing systems face high costs and noise issues due to the use of external multiplexers and traditional multiplexing methods, which require numerous cables and relays, leading to increased expense and potential component damage from stray capacitance.
Innovation Solution
The use of manually programmable jumper blocks for probe contact selection reduces multiplexing requirements by fixing device configurations, limiting the need for dynamic changes and minimizing the number of relays required, allowing for cost-effective signal routing through fixed jumper blocks.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If an external multiplexer is used to route test signals to a wafer prober, then signal multiplexing capability is achieved, but cable length increases and noise pickup increases
Solution Approach 1:
The patent extracts the multiplexing function from the external multiplexer and relocates it directly into the wafer prober's probe card. By integrating the multiplexer onto the probe card, the long external cables are eliminated, thereby removing the source of noise pickup while preserving the signal multiplexing capability across multiple device pins.
Solution Approach 2:
The multiplexer is nested within the probe card structure itself, with the probe card containing both the testing function and the multiplexing function. This nested arrangement allows the multiplexer to be physically co-located with the devices being tested, eliminating the need for separate external multiplexing equipment and associated cabling.
2Adaptability or versatility
If an external multiplexer is used to route test signals, then signal multiplexing is achieved, but stray capacitance increases which can damage components
Solution Approach 1:
The patent removes the external multiplexer and its associated cables from the system, extracting the harmful stray capacitance effect along with it. By implementing the multiplexer directly on the probe card, the signal paths are shortened and isolated, eliminating the stray capacitance that would otherwise be introduced by long external connections.
3Adaptability or versatility
If traditional multiplexing is used on the probe card, then signal multiplexing is achieved, but the number of relays and switches increases which increases expense
Solution Approach 1:
The patent replaces the traditional mechanical relay-based multiplexing system with a solid-state switching architecture integrated into the probe card. This substitution eliminates the need for numerous mechanical relays and switches, reducing component count, lowering cost, and simplifying the overall system while maintaining full multiplexing functionality.
4Adaptability or versatility
If device configurations are dynamically changed during testing, then adaptability is improved, but the number of relays required increases
Solution Approach 1:
The patent applies preliminary action by pre-configuring the probe card's multiplexer settings before testing begins. The device configurations are established in advance through programmed control, eliminating the need for dynamic relay switching during the actual testing process. This approach maintains adaptability while minimizing the number of relays required.
Data Source
AI summary
A semi-automatic multiplexing system for automated semiconductor wafer testing employs a jumper block for each device type in the semiconductor wafer to be tested, each jumper block having inputs for receiving a test input/output line, a plurality of block contacts corresponding to pads of a device to be tested, and manually set connectors or jumper cables for selectively interconnecting jumper block inputs to block contacts. A multiplexer is then used for selectively connecting tester input/output lines to the jumper blocks, thereby reducing the number of relays required for connecting test signals to the devices in the semiconductor wafer.