Semiconductor Device With Bent Substrate For Carrier Mobility
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
In semiconductor devices, particularly NAND type non-volatile memory devices, the mobility of carriers in the channel region is reduced due to the increased number of cell transistors, leading to inefficient voltage transmission and carrier movement.
Innovation Solution
A semiconductor device design where a first substrate with cell transistors is attached to a second substrate with a bent upper surface, applying tensile stresses to improve carrier mobility, utilizing substrates with specific crystal planes and layer structures such as tunnel oxide, floating gate, and charge trapping layers, and using an adhesive like epoxy resin for attachment.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Quantity of substance
If the number of cell transistors is increased, then the storage capacity is improved, but the voltage transmission efficiency deteriorates
Solution Approach 1:
The invention divides the substrate into multiple segments by introducing intermediate substrates with bent surfaces between peripheral and central cell transistors. Each substrate segment can independently transmit voltage, ensuring that even as the total number of cell transistors increases, the voltage transmission path remains efficient through segmented intermediate substrates.
2Quantity of substance
If the number of cell transistors is increased, then the storage capacity is improved, but the carrier mobility deteriorates
Solution Approach 1:
The invention changes the physical parameters of the substrate by introducing bent surfaces with specific curvatures on intermediate substrates. This geometric parameter change generates tensile stress that directly improves carrier mobility in the channel region, allowing high-speed carrier transport even when the number of cell transistors is increased.
3Ease of manufacture
If a flat substrate structure is used, then the manufacturing simplicity is maintained, but the carrier mobility is reduced
Solution Approach 1:
The invention introduces curved surfaces on intermediate substrates instead of flat surfaces. The bent surface configuration generates tensile stress in the underlying substrate, which improves carrier mobility. This curvature is implemented through controlled bending during the manufacturing process, maintaining ease of manufacture while achieving the desired stress effect.
4Stability of the object's composition
If no stress is applied to the substrate, then the structural stability is maintained, but the carrier mobility is reduced
Solution Approach 1:
The invention carefully controls the bending parameter of intermediate substrates to generate optimal tensile stress. By adjusting the curvature radius and bending degree, the substrate receives sufficient tensile stress to improve carrier mobility while maintaining overall structural stability through controlled stress distribution.
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 design significantly enhances carrier mobility and capacitance in the channel region, ensuring efficient voltage transmission and improved operational characteristics of the cell transistors.
Implementation Method 1
the upper surface of the second substrate has a bent structure to apply tensile stresses to the first substrate in the extending direction of the plurality of cell transistors
Data Source
AI summary
A semiconductor device includes a first substrate, a plurality of cell transistors and a second substrate. The first substrate has a first surface and a second surface opposite to the first surface. The plurality of cell transistors is formed extending on the first surface of the first substrate in a direction. The second substrate has an upper surface making contact with the second surface of the first substrate. Further, the upper surface of the second substrate has a bent structure to apply tensile stresses to the first substrate in the extending direction of the plurality of cell transistors. Thus, tensile stresses may be applied to the first substrate to improve the mobility of carriers in a channel region of the cell transistors.