FinFET One-Time Programmable Memory With Shared Channel
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional one-time programmable (OTP) semiconductor devices are costly and incompatible with emerging FinFET architectures, requiring additional processing steps and circuit area for programming and sensing, which is not compatible with FinFET fabrication processes at the 22 nm technology node and beyond.
Innovation Solution
A FinFET-based OTP device is designed with two monolithically integrated FinFETs sharing a common source, drain, and channel region, where one FinFET is used for programming and the other for sensing, allowing for self-sensing through altered threshold voltage and drain current detection, eliminating the need for separate sensing devices and additional processing steps.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Device complexity
If conventional OTP device architecture with separate sensing transistor is used, then programming and sensing functions are provided, but device complexity and circuit area increase
Solution Approach 1:
The patent combines the sensing transistor and programming element into a single FinFET structure. The FinFET channel serves dual purposes: as the sensing element that detects programming state and as the programming target where threshold voltage is modified. This integration eliminates the need for separate sensing and programming components, directly reducing device complexity while maintaining both programming and sensing functions.
Solution Approach 2:
The FinFET structure is designed to perform multiple functions simultaneously. The same FinFET channel region is used for both sensing (detecting threshold voltage changes) and programming (applying high voltage to modify threshold voltage). This multi-functionality approach allows a single structure to replace what would traditionally require separate dedicated components, thereby reducing overall device complexity.
2Ease of manufacture
If additional processing steps beyond conventional transistor fabrication are used, then OTP functionality is achieved, but manufacturing cost increases
Solution Approach 1:
The FinFET structure is designed to be fabricated using standard FinFET fabrication processes without requiring additional specialized steps. The same process steps that create the FinFET transistor are used to create the OTP functionality, making the OTP device a natural extension of conventional FinFET manufacturing rather than a separate process requiring additional cost.
Solution Approach 2:
The FinFET structure inherently provides both sensing and programming capabilities through its own physical properties and response to voltage application. The structure serves itself by using its channel region for both detection and modification purposes, eliminating the need for external specialized processing steps or additional components that would increase manufacturing complexity and cost.
3Area of stationary object
If separate sensing device is used, then programming state detection is provided, but circuit area increases
Solution Approach 1:
The sensing function is merged into the FinFET channel itself rather than requiring a separate sensing device. The channel region that would traditionally be dedicated to sensing is integrated with the programming element, creating a unified structure that performs both functions in the same physical space, thereby reducing the total circuit area occupied.
4Adaptability or versatility
If conventional OTP architecture is used, then programming element and transistor are provided, but compatibility with FinFET architecture is lost
Solution Approach 1:
The invention adapts the OTP concept to FinFET architecture by utilizing FinFET-specific parameters and characteristics. The high voltage application for programming exploits the FinFET's ability to withstand and respond to voltage stress on its channel, while the sensing function utilizes the FinFET's threshold voltage modulation characteristics. This parameter-based adaptation ensures compatibility with FinFET fabrication and operation while maintaining reliable programming element function.
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
This approach results in a compact, reliable, and cost-effective OTP device that is compatible with FinFET fabrication processes, avoiding damage to the sensing device during programming and enabling seamless integration with existing FinFET transistor fabrication without additional processing steps.
Implementation Method 1
The thinner portion of gate dielectric can be made to destructively break down and form a conductive path from the extended gate to the underlying channel
Data Source
AI summary
According to one embodiment, a one-time programmable (OTP) device comprises a memory FinFET in parallel with a sensing FinFET. The memory FinFET and the sensing FinFET share a common source region, a common drain region, and a common channel region. The memory FinFET is programmed by having a ruptured gate dielectric, resulting in the sensing FinFET having an altered threshold voltage and an altered drain current. A method for utilizing such an OTP device comprises applying a programming voltage for rupturing the gate dielectric of the memory FinFET thereby achieving a programmed state of the memory FinFET, and detecting by the sensing FinFET the altered threshold voltage and the altered drain current due to the programmed state of the memory FinFET.