Single Fin Doping Profile for Stress Reduction

Solution Overview

Problem

The formation of single semiconductor fins in FinFETs for advanced technology nodes is challenging due to lack of support, leading to stress-related structural failures and increased current leakage caused by n-well implants in pFET devices.

Innovation Solution

An integrated circuit structure with a single active region having a first doping profile and a set of active regions with a second doping profile, where the second profile is deeper and has a higher dopant concentration, electrically isolated from the single active region to reduce the extent and number of n-well implants, thereby minimizing defects and stress-related failures.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Ease of manufacture

If n-well implants are performed in single semiconductor fin for pFET devices, then device formation is enabled, but stress-related structural failures and current leakage occur

Engineering Contradiction:

Improvedevice formationVSAvoidstructural integrity

Core Design Contradiction:

Ease of manufactureVSReliability

Solution Approach 1:

The patent segments the fins into two distinct groups: a first set of fins with a first doping profile and a second set of fins with a second doping profile. This segmentation allows the single fin to be electrically isolated from neighboring fins through different doping characteristics, preventing stress propagation while enabling controlled n-well implantation where needed.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The patent applies different doping profiles to different sets of fins based on their specific device requirements. The single fin receives a tailored doping profile that differs from the multi-fin arrangements, allowing localized optimization of stress management and electrical isolation for low-power devices while maintaining standard processing for other regions.

Inventive Principle:

Principle #3Local quality

2Use of energy by moving object

If single semiconductor fin is used for low power devices, then power consumption is reduced, but support structure is lacking leading to manufacturing challenges

Engineering Contradiction:

Improvepower consumptionVSAvoidmanufacturing process

Core Design Contradiction:

Use of energy by moving objectVSEase of manufacture

Solution Approach 1:

The patent changes the doping parameters (concentration, depth, profile shape) specifically for the single fin used in low-power devices compared to standard multi-fin configurations. This parameter adjustment provides the single fin with adequate electrical isolation and stress management without requiring additional physical support structures, thereby simplifying the manufacturing process while maintaining low power characteristics.

Inventive Principle:

Principle #35Parameter changes

3Reliability

If n-well implants are reduced in single active region, then defects and stress failures are minimized, but device functionality must be maintained

Engineering Contradiction:

Improvedefect reductionVSAvoiddevice functionality

Core Design Contradiction:

ReliabilityVSAdaptability or versatility

Solution Approach 1:

The patent applies different doping profiles to different sets of fins based on their specific device requirements. The single fin receives a tailored doping profile that differs from the multi-fin arrangements, allowing localized optimization of stress management and electrical isolation for low-power devices while maintaining standard processing for other regions.

Inventive Principle:

Principle #3Local quality

Solution Approach 2:

The patent changes the doping parameters (concentration, depth, profile shape) specifically for the single fin used in low-power devices compared to standard multi-fin configurations. This parameter adjustment provides the single fin with adequate electrical isolation and stress management without requiring additional physical support structures, thereby simplifying the manufacturing process while maintaining low power characteristics.

Inventive Principle:

Principle #35Parameter changes

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 allows for the creation of reliable single semiconductor finFETs for low power devices at advanced technology nodes, reducing defects and performance degradation such as current leakage in p-finFETs by minimizing the impact of n-well implants.

Implementation Method 1

first doping the set of active regions and the single active region, creating a first doping profile in the set of active regions and the single active region; masking the single active region, leaving the set of active regions exposed; and second doping the set of active regions, creating a second doping profile in the set of active regions that is different than the first doping profile of the single active region

Methodology Applied

Scientific EffectDoping: Dopants

Data Source

PatentUS11205648B2IC structure with single active region having different doping profile than set of active regions

Publication Date: 2021.12.21 GLOBALFOUNDRIES US INC

AI summary

An integrated circuit (IC) structure with a single active region having a doping profile different than that of a set of active regions, is disclosed. The IC structure provides a single active region, e.g., a fin, on a substrate with a first doping profile, and a set of active regions, e.g., fins, electrically isolated from the single active region on the substrate. The set of active regions have a second doping profile that is different than the first doping profile of the single active region. For example, the second doping profile can have a deeper penetration into the substrate than the first doping profile.