Semiconductor Substrate Biasing for Leakage Reduction
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Semiconductor device structures with bulk substrates face issues of high capacitance and body-to-body leakage, which are not adequately addressed by traditional triple well isolation or silicon-on-insulator substrates, as they either compromise linearity or are costly.
Innovation Solution
A substrate contact is coupled to a bulk semiconductor substrate and configured to apply a negative bias voltage, electrically isolating the semiconductor body from the substrate, thereby reducing leakage current without the need for expensive silicon-on-insulator substrates or triple well isolation.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If triple well isolation is used to reduce body-to-body leakage, then leakage is reduced, but device linearity deteriorates
Solution Approach 1:
The patent changes the electrical parameter of the substrate by applying a negative bias voltage to the substrate contact. This parameter change creates a reverse-biased junction that reduces body-to-body leakage current while maintaining device linearity, avoiding the need for triple well isolation structures.
2Reliability
If silicon-on-insulator substrate is used to reduce body-to-body leakage, then leakage is reduced, but manufacturing cost increases
Solution Approach 1:
The patent replaces the expensive silicon-on-insulator substrate with a bulk semiconductor substrate combined with a simple substrate contact structure. This cheaper alternative achieves the same leakage reduction function through negative biasing, eliminating the need for costly SOI fabrication processes.
3Ease of manufacture
If bulk semiconductor substrate is used, then manufacturing cost is reduced, but capacitance increases
Solution Approach 1:
The patent applies a negative bias voltage to the substrate contact, which changes the electrical state of the bulk substrate. This creates a depletion region that reduces the effective capacitance between the body and substrate, allowing bulk substrates to be used without suffering from high capacitance effects.
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 effectively reduces leakage current while maintaining device linearity, avoiding the cost and complexity of silicon-on-insulator substrates and triple well isolation schemes.
Implementation Method 1
The substrate contact is configured to be biased with a negative bias voltage
Implementation Method 2
The semiconductor body is electrically isolated from the portion of the bulk semiconductor substrate
Data Source
AI summary
Semiconductor device structures with substrate biasing, methods of forming a semiconductor device structure with substrate biasing, and methods of operating a semiconductor device structure with substrate biasing. A substrate contact is coupled to a portion of a bulk semiconductor substrate in a device region. The substrate contact is configured to be biased with a negative bias voltage. A field-effect transistor includes a semiconductor body in the device region of the bulk semiconductor substrate. The semiconductor body is electrically isolated from the portion of the bulk semiconductor substrate.