FeRAM Capacitor Leaker Structure for Read Disturb Suppression
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Read disturb errors in memory cells due to excess charge accumulation at the bottom electrode of capacitors in ferroelectric RAM (FeRAM) devices, leading to unreliable data retrieval and potential depolarization of stored states.
Innovation Solution
Incorporating leaker devices with controlled resistance to dissipate excess charge from the bottom electrode to the cell plate, while ensuring uniform electrical properties across different leaker devices to enhance memory device reliability and manufacturing yield.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If leaker devices are added to dissipate excess charge from bottom electrodes, then read disturb errors are reduced, but device complexity increases
Solution Approach 1:
The leaker device is merged with the cell plate structure by forming the leaker device within the cell plate opening. The cell plate serves dual purposes: as a common electrode for multiple memory cells and as a collection point for excess charge dissipation through the integrated leaker device. This integration reduces the need for separate charge dissipation structures.
Solution Approach 2:
The cell plate is given multi-functionality by incorporating the leaker device within it. The cell plate not only serves as a common electrode for multiple memory cells but also functions as a charge dissipation path through the integrated leaker device, eliminating the need for dedicated charge dissipation structures.
2Productivity
If leaker devices are formed with varying electrical properties to match process variations, then manufacturing yield improves, but measurement precision requirements increase
Solution Approach 1:
The electrical properties of the leaker device, specifically the resistance value, are adjusted to compensate for process variations. By changing the resistance parameter of the leaker device, the patent ensures that excess charge dissipation remains effective across different manufacturing batches and process conditions, thereby improving manufacturing yield.
3Reliability
If the leaker device resistance is reduced to dissipate charge faster, then read disturb errors are reduced, but excess charge dissipation increases energy consumption
Solution Approach 1:
The leaker device provides a controlled path for excess charge dissipation rather than completely discharging all charge. The resistance is optimized to allow sufficient charge dissipation to prevent read disturb errors while minimizing unnecessary energy consumption. This partial action approach balances reliability improvement with energy efficiency.
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
The implementation of leaker devices effectively reduces read disturb errors and process variation, resulting in more robust and reliable memory device operation by maintaining appropriate charge and polarity for data storage.
Implementation Method 1
leaker devices with controlled resistance to dissipate excess charge from the bottom electrode to the cell plate
Data Source
AI summary
Implementations described herein relate to various structures, integrated assemblies, and memory devices. In some implementations, an integrated assembly includes a cell plate, a pillar that includes a bottom electrode and a leaker device on top of the bottom electrode, and a top electrode. The top electrode includes a first top electrode portion and a second top electrode portion. The first top electrode portion is separated from the bottom electrode by the leaker device. The second top electrode portion is separated from the bottom electrode and the leaker device by an insulator. The leaker device is configured to discharge excess charge from the bottom electrode to the cell plate via the first top electrode portion.