RRAM Memory Structure Using Titanium Oxynitride and Dual Barrier Layers
Solution Overview
Problem
Resistive random access memory (RRAM) devices face challenges in achieving improved retention time, endurance, and sensing window due to limitations in materials used for memory elements and barrier layers.
Innovation Solution
A semiconductor structure comprising a memory element made of titanium oxynitride, with a first barrier layer of silicon or silicon oxide and a second barrier layer of titanium or titanium oxide, enhancing the performance by improving retention and endurance, and expanding the sensing window.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Duration of action of stationary object
If conventional materials are used for memory elements and barrier layers, then device structure is simple, but retention time and endurance are insufficient
Solution Approach 1:
The patent employs composite material structures where the memory element uses titanium oxynitride combined with barrier layers of silicon oxide and titanium oxide. This composite approach leverages the complementary properties of each material: titanium oxynitride provides resistive switching functionality with improved retention, while the silicon oxide and titanium oxide barrier layers enhance endurance by preventing material diffusion and maintaining structural integrity during repeated write/erase cycles.
Solution Approach 2:
The patent optimizes the compositional parameters of the titanium oxynitride memory element, specifically controlling the oxygen and nitrogen content ratios to achieve optimal resistive switching characteristics. By adjusting these chemical parameters, the memory element achieves both long retention time (improving parameter 16) and high endurance (improving parameter 27), resolving the technical contradiction between these two reliability metrics.
2Reliability
If materials are optimized for larger sensing window, then performance improves, but device complexity increases
Solution Approach 1:
The patent segments the barrier structure into two distinct layers: a silicon oxide barrier layer adjacent to the titanium oxynitride memory element, and a titanium oxide barrier layer on the outer side. This segmentation allows each layer to perform its specific function optimally - silicon oxide provides excellent interface quality with titanium oxynitride for large sensing window, while titanium oxide provides robust chemical stability. The segmented structure achieves high performance without excessive complexity by assigning specific roles to each layer.
Solution Approach 2:
The patent applies local quality optimization by selecting different barrier materials for different positions in the stack. The silicon oxide layer is placed where it provides maximum benefit for sensing window (at the interface with titanium oxynitride), while titanium oxide is placed where chemical stability is most critical (outer barrier layer). This position-specific material selection achieves optimal sensing window without uniformly increasing device complexity throughout the entire structure.
Data Source
AI summary
A semiconductor structure includes a memory structure. The memory structure includes a memory element, a first barrier layer and a second barrier layer. The memory element includes titanium oxynitride. The first barrier layer includes at least one of silicon and silicon oxide. The first barrier layer is disposed on the memory element. The second barrier layer includes at least one of titanium and titanium oxide. The second barrier layer is disposed on the first barrier layer.