Semiconductor Storage Device Backside Transistor Threshold Control
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current semiconductor storage devices face challenges in achieving high reliability and simplicity in data reading, particularly in the power-on-read area where data is read immediately after power is applied, due to the need for complex voltage control and potential interference from backside cell transistors.
Innovation Solution
The semiconductor storage device design includes a configuration where backside cell transistors have a threshold voltage higher than the read voltage, ensuring they remain in an OFF state during data reading, eliminating the need for negative read voltages and simplifying the circuitry, and allowing for high-reliability data retrieval.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If conventional reading methods are used in power-on-read area, then data can be read, but complex voltage control is required and interference from backside cell transistors occurs
Solution Approach 1:
The patent changes the threshold voltage parameter of backside cell transistors to be higher than the read voltage, ensuring they remain in an OFF state during data reading operations. This parameter modification eliminates the need for complex negative voltage control while preventing interference from backside transistors, thus resolving the contradiction between reading reliability and control complexity
2Productivity
If backside cell transistors are activated during reading, then more transistors can be utilized, but interference with data reading occurs
Solution Approach 1:
The patent applies different threshold voltage characteristics to different transistor groups: backside cell transistors have threshold voltages higher than read voltage (remaining OFF), while frontside cell transistors have threshold voltages lower than read voltage (remaining ON). This local differentiation allows selective activation, preventing interference while maximizing transistor utilization for data storage and reading
Data Source
AI summary
A semiconductor storage device includes a first semiconductor extending above a substrate and including a first part and a second part, a first word line at a first level above the substrate and facing the first part of the first semiconductor, a second word line at the first level above the substrate and facing the second part of the first semiconductor, a first cell transistor including a first area of the first part of the first semiconductor that faces the first word line, and a second cell transistor including a second area of the second part of the first semiconductor that faces the second word line, wherein during an operation of reading data from the first cell transistor, a first voltage that is less than a threshold voltage of the second cell transistor and greater than or equal to zero voltage is applied to the second word line.