Semiconductor Structure Integrating Active Power Devices and Passive Components

Solution Overview

Problem

Integrating high-frequency, high-power active power devices with passive components on the same substrate is challenging due to the mutually exclusive design criteria of low-resistivity substrates for active devices and high-resistivity substrates for passive components, leading to issues with parasitic impedance and RF noise.

Innovation Solution

A method of forming a semiconductor structure with a high-resistivity substrate for passive components and a low-resistivity region for active power devices, where passive components are integrated laterally relative to active devices and electrically connected, using a shielding structure as a second gate to control operational modes and incorporating an integrated source bypass capacitor and inductor to reduce parasitic impedance.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If a low-resistivity substrate is used for active power devices, then the active devices achieve high-frequency performance, but passive components experience increased parasitic impedance and reduced RF performance

Engineering Contradiction:

Improveactive device performanceVSAvoidparasitic impedance

Core Design Contradiction:

ReliabilityVSObject-affected harmful factors

Solution Approach 1:

The substrate is divided into two distinct regions: a first substrate region with first resistivity for passive components and a second substrate region with second resistivity for active power devices. This segmentation allows each region to be optimized independently - the low-resistivity region supports high-frequency active devices while the high-resistivity region minimizes parasitic impedance for passive components, thereby resolving the contradiction between active device performance and passive component performance.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

Different resistivity characteristics are assigned to different locations within the substrate. The substrate exhibits non-uniform electrical properties, with low-resistivity zones positioned to support active power devices and high-resistivity zones positioned to support passive components. This local quality variation enables simultaneous optimization of both active and passive device performance on the same substrate.

Inventive Principle:

Principle #3Local quality

2Object-affected harmful factors

If a high-resistivity substrate is used for passive components, then parasitic impedance is reduced, but active power devices cannot achieve optimal high-frequency performance

Engineering Contradiction:

Improveparasitic impedanceVSAvoidactive device performance

Core Design Contradiction:

Object-affected harmful factorsVSReliability

Solution Approach 1:

The substrate is divided into two distinct regions: a first substrate region with first resistivity for passive components and a second substrate region with second resistivity for active power devices. This segmentation allows each region to be optimized independently - the low-resistivity region supports high-frequency active devices while the high-resistivity region minimizes parasitic impedance for passive components, thereby resolving the contradiction between active device performance and passive component performance.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

Different resistivity characteristics are assigned to different locations within the substrate. The substrate exhibits non-uniform electrical properties, with low-resistivity zones positioned to support active power devices and high-resistivity zones positioned to support passive components. This local quality variation enables simultaneous optimization of both active and passive device performance on the same substrate.

Inventive Principle:

Principle #3Local quality

3Reliability

If GaAs substrate is used for high-frequency operation, then carrier mobility and parasitic capacitance are optimized, but integration with other devices on the same die becomes difficult

Engineering Contradiction:

Improvehigh-frequency performanceVSAvoidintegration difficulty

Core Design Contradiction:

ReliabilityVSDevice complexity

Solution Approach 1:

The invention employs a composite substrate structure combining silicon regions with different resistivity values. Rather than using a single material type (GaAs) throughout, the substrate integrates multiple silicon regions with tailored electrical properties - low-resistivity regions for active devices and high-resistivity regions for passive components. This composite approach maintains the benefits of high-frequency operation while enabling seamless integration of both active and passive devices using compatible fabrication processes.

Inventive Principle:

Principle #40Composite materials

Data Source

PatentUS9704855B2Integration of active power device with passive components

Publication Date: 2017.07.11 COOLSTAR TECH

AI summary

A method of integrating at least one passive component and at least one active power device on a same substrate includes: forming a substrate having a first resistivity value associated therewith; forming a low-resistivity region having a second resistivity value associated therewith in the substrate, the second resistivity value being lower than the first resistivity value; forming the at least one active power device in the low-resistivity region; forming an insulating layer over at least a portion of the at least one active power device; and forming the at least one passive component on an upper surface of the insulating layer above the substrate having the first resistivity value, the at least one passive component being disposed laterally relative to the at least one active power device and electrically connected with the at least one active power device.