Semiconductor Memory Device Program Voltage Pulse Width Adjustment

Solution Overview

Problem

Semiconductor memory devices face challenges in maintaining data reliability due to increased program operation speed leading to potential deterioration in data integrity as the number of program/erase operations increases, if performed with a constant program voltage.

Innovation Solution

The method involves adjusting the pulse width or duration of the program voltage based on the number of program/erase operations, with the pulse width or duration decreasing as the number of operations increases, to maintain data reliability.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Productivity

If the program operation speed is increased, then the productivity is improved, but the data reliability deteriorates as the number of program/erase operations increases

Engineering Contradiction:

Core Design Contradiction:

ProductivityVSReliability

Solution Approach 1:

The program voltage pulse width is dynamically adjusted based on the number of program/erase operations performed. As the operation count increases, the pulse width is decreased to prevent data integrity deterioration. This dynamic adaptation allows the system to maintain high productivity while preserving data reliability through conditional parameter modification.

Inventive Principle:

Principle #15Dynamics

Solution Approach 2:

The invention changes the parameter of program voltage pulse width according to the number of program/erase operations. By modifying this electrical parameter adaptively, the system resolves the contradiction between maintaining fast program operations and ensuring data reliability over multiple erase cycles.

Inventive Principle:

Principle #35Parameter changes

2Ease of operation

If a constant program voltage pulse width is used, then the ease of operation is improved, but the data reliability worsens with increasing program/erase operations

Engineering Contradiction:

Core Design Contradiction:

Ease of operationVSReliability

Solution Approach 1:

The system automatically adjusts the program voltage pulse width based on the stored count of program/erase operations without requiring external intervention. The controller reads the operation count from storage and autonomously modifies the voltage parameters, maintaining data reliability while keeping the operation process simple and automated.

Inventive Principle:

Principle #25Self-service

Solution Approach 2:

The system implements feedback by reading the number of program/erase operations from storage and using this information to adjust subsequent program voltage parameters. This closed-loop approach ensures data integrity is maintained while keeping the control mechanism automated and straightforward.

Inventive Principle:

Principle #23Feedback

Data Source

PatentUS8848448B2Semiconductor memory device and operating method thereof

Publication Date: 2014.09.30

AI summary

A semiconductor memory device and a method of operating same includes reading a number of program/erase operations stored in a program/erase number storage unit, setting a pulse width of a program voltage based on the read number of program/erase operations, and performing a program operation on memory cells using the program voltage having the set pulse width. Setting of the pulse width of the program voltage includes decreasing the pulse width of the program voltage as the number of program/erase operations increases.