Integrated Pulse Circuit for Thin Gate Oxide Capacitance Measurement

Solution Overview

Problem

Current charge-based capacitance measurement (CBCM) and charge pumping methods face challenges in measuring low-frequency capacitance of thin gate insulating films, requiring external pulse generators and increasing mounting area and PADs due to differing optimum frequencies for CBCM and CP methods.

Innovation Solution

A semiconductor integrated circuit with a pulse generation circuit capable of frequency modulation, branching pulses to CBCM and DCBCM circuits, and non-measurement MISFETs, allowing for internal pulse generation and phase synchronization, eliminating the need for external generators and enabling simultaneous CBCM and CP method implementation.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Measurement precision

If external pulse generators are used for CBCM and CP methods, then measurement capability is improved, but mounting area and number of PADs increase

Engineering Contradiction:

Improvecapacitance measurement accuracyVSAvoidmounting area

Core Design Contradiction:

Measurement precisionVSArea of stationary object

Solution Approach 1:

The patent combines the CBCM circuit and CP circuit into a single integrated circuit structure that shares common components including the pulse generation circuit, PADs, and substrate. This merging eliminates the need for separate external pulse generators and reduces the overall mounting area while maintaining both measurement capabilities

Inventive Principle:

Principle #5Merging (Combining)

Solution Approach 2:

The integrated circuit is designed with multi-functionality where a single circuit structure performs both CBCM and CP measurement functions. The pulse generation circuit and PADs serve dual purposes for both measurement methods, reducing the number of required components and mounting area

Inventive Principle:

Principle #6Universality (Multi-functionality)

2Measurement precision

If external pulse generators are used for CBCM and CP methods, then measurement capability is improved, but the number of PADs increases

Engineering Contradiction:

Improvecapacitance measurement accuracyVSAvoidnumber of PADs

Core Design Contradiction:

Measurement precisionVSQuantity of substance

Solution Approach 1:

The patent combines the CBCM circuit and CP circuit into a single integrated circuit structure that shares common components including the pulse generation circuit, PADs, and substrate. This merging eliminates the need for separate external pulse generators and reduces the overall mounting area while maintaining both measurement capabilities

Inventive Principle:

Principle #5Merging (Combining)

Solution Approach 2:

The integrated circuit is designed with multi-functionality where a single circuit structure performs both CBCM and CP measurement functions. The pulse generation circuit and PADs serve dual purposes for both measurement methods, reducing the number of required components and mounting area

Inventive Principle:

Principle #6Universality (Multi-functionality)

3Ease of operation

If standard mass-production line measuring system is used, then ease of operation is improved, but measurement capability for thin gate insulating films is lost

Engineering Contradiction:

Improvemass production compatibilityVSAvoidlow frequency capacitance measurement accuracy

Core Design Contradiction:

Ease of operationVSMeasurement precision

Solution Approach 1:

The integrated circuit incorporates internal pulse generation capability within the circuit structure itself, eliminating the need for external pulse generators that are not available in standard mass-production line measuring systems. The circuit serves itself by generating the necessary measurement pulses internally

Inventive Principle:

Principle #25Self-service

Solution Approach 2:

The patent combines the CBCM circuit and CP circuit into a single integrated circuit structure that shares common components including the pulse generation circuit, PADs, and substrate. This merging eliminates the need for separate external pulse generators and reduces the overall mounting area while maintaining both measurement capabilities

Inventive Principle:

Principle #5Merging (Combining)

Data Source

PatentUS10782330B2Semiconductor integrated circuit and signal processing method

Publication Date: 2020.09.22 SONY GROUP CORP

AI summary

The present disclosure relates to a semiconductor integrated circuit and a signal processing method that can improve measurement accuracy. Pulses subjected to pulse generation and disconnection control by a control circuit are supplied to a pulse distribution circuit and a CP circuit. The pulse distribution circuit divides one pulse into two or more pulses that do not overlap each other, and supplies the pulses to a CBCM circuit. The CBCM circuit is configured by connecting a capacitance element to be measured to the output of a measurement core circuit called a pseudo inverter. The CP circuit inputs, to the gate electrode, pulses that cause a channel of a non-measurement MISFET to change from the accumulation state to the inverted state, and monitors, from the substrate side, a CP current flowing through a trap acting as a recombination center of the gate insulating film and the semiconductor substrate interface. The present disclosure can be applied to, for example, a semiconductor integrated circuit for evaluating the characteristics of the gate insulating film of the MISFET.