3D Flash Memory Hole Injection Erase via P-type Filler
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional 3D flash memory using IGZO as a channel layer cannot support the hole injection erase technique due to high hole effective mass and low hole mobility, leading to increased leakage current and deteriorated cell characteristics as the number of vertically stacked stages increases.
Innovation Solution
A 3D flash memory structure is developed where the inner space of a hollow macaroni-shaped channel layer is filled with a P-type filler, with adjustable doping concentration and a nitride layer interposed between the P-type filler and the channel layer to suppress leakage current, enabling hole injection erase technique support.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Object-generated harmful factors
If IGZO material is used as channel layer to reduce leakage current, then leakage current is reduced, but hole injection erase technique cannot be supported due to high hole effective mass and low hole mobility
Solution Approach 1:
A P-type filler is introduced as an intermediary substance between the IGZO channel layer and the control electrode. This filler has high hole mobility that compensates for the IGZO material's low hole mobility, enabling hole injection erase technique while the IGZO layer continues to provide low leakage current characteristics.
Solution Approach 2:
The channel structure is formed as a composite of IGZO material and P-type filler. The IGZO provides the low leakage current property while the P-type filler provides high hole mobility, creating a composite structure that exhibits both desired characteristics simultaneously.
2Productivity
If the number of vertically stacked stages is increased to increase integration density, then integration density is improved, but cell characteristics deteriorate due to increased leakage current
Solution Approach 1:
The hole mobility parameter of the channel structure is fundamentally changed by introducing P-type filler, which has inherently high hole mobility. This parameter change allows the channel to maintain low leakage current even as the number of vertically stacked stages increases, thereby maintaining cell characteristics while improving integration density.
3Adaptability or versatility
If P-type filler is added to enable hole injection erase technique, then hole injection erase technique is supported, but device complexity increases
Solution Approach 1:
The P-type filler is nested within the hollow macaroni-shaped channel structure, filling the inner space of the channel. This nested configuration enables hole injection erase technique without requiring separate external structures, as the filler is integrated within the existing channel geometry.
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 proposed structure effectively supports the hole injection erase technique while preventing leakage current, maintaining cell characteristics by using a P-type filler with optimized doping concentration and trap density, and a nitride layer for blocking leakage.
Implementation Method 1
The P-type filer may support a hole injection erase technique by supplying a voltage applied from the substrate to an entire area of the channel layer
Implementation Method 2
a nitride layer interposed between the P-type filler and the channel layer to suppress leakage current
Data Source
AI summary
Disclosed are a three-dimensional flash memory, which reduces leakage current and supports a hole injection erase technique, and a method for manufacturing same. According to an embodiment, the three-dimensional flash memory comprises: a substrate; a channel layer extending in one direction on the substrate and having the shape of a hollow macaroni; and a P-type filer extending in the one direction while filling the inner space of the channel layer.