CN118711640A - A method and device for improving low temperature reliability and read performance of 3-D flash memory based on read reference voltage calibration - Google Patents
A method and device for improving low temperature reliability and read performance of 3-D flash memory based on read reference voltage calibration Download PDFInfo
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Abstract
一种基于读参考电压校准的3‑D闪存低温可靠性和读取性能提升方法及装置，涉及固态存储领域。为解决现有技术中尚未公开一种在低温环境下有效提升闪存的可靠性和读取性能的技术方案的缺陷，本发明提供的技术方案为：闪存低温可靠性提升模型建立方法，所述方法包括：采集闪存在不同温度下的阈值电压偏移数据集，并预处理的步骤；根据预处理后的所述阈值电压偏移数据集的数据，得到不同温度与最优读参考电压偏移之间的初步关系模型的步骤；根据预设的所述闪存的影响因素，对所述初步关系模型进行修正，得到修正模型的步骤；根据所述修正模型和所述影响因素，建立综合补偿模型的步骤。适合应用于NAND Flash的读参考电压校准的工作中。
A method and device for improving the low-temperature reliability and reading performance of 3-D flash memory based on read reference voltage calibration, relating to the field of solid-state storage. In order to solve the defect that a technical solution for effectively improving the reliability and reading performance of flash memory in a low-temperature environment has not yet been disclosed in the prior art, the technical solution provided by the present invention is: a method for establishing a low-temperature reliability improvement model for flash memory, the method comprising: collecting a threshold voltage offset data set of flash memory at different temperatures and preprocessing the data set; obtaining a preliminary relationship model between different temperatures and the optimal read reference voltage offset based on the data of the preprocessed threshold voltage offset data set; correcting the preliminary relationship model according to the preset influencing factors of the flash memory to obtain a corrected model; and establishing a comprehensive compensation model based on the corrected model and the influencing factors. It is suitable for application in the work of NAND Flash read reference voltage calibration.
Description
技术领域Technical Field
涉及固态存储领域，具体涉及NAND Flash的读参考电压校准。The invention relates to the field of solid-state storage, and in particular to a read reference voltage calibration of a NAND Flash.
背景技术Background Art
随着信息技术的飞速发展，闪存作为一种高密度、高可靠性的非易失性存储介质，在消费电子市场中得到了广泛应用。特别是3-D NAND闪存技术的出现，以其超高的存储密度、低功耗和高性能等优势，成为智能手机、平板电脑、智能穿戴设备、汽车电子等消费电子设备的理想选择。这些设备通常在非固定的工作环境中使用，经常面临温度波动的挑战，尤其是在低温环境下，温度变化对闪存的性能和可靠性构成了显著影响。With the rapid development of information technology, flash memory, as a high-density, high-reliability non-volatile storage medium, has been widely used in the consumer electronics market. In particular, the emergence of 3-D NAND flash memory technology, with its ultra-high storage density, low power consumption and high performance, has become an ideal choice for consumer electronic devices such as smartphones, tablets, smart wearable devices, and automotive electronics. These devices are usually used in non-fixed working environments and often face the challenge of temperature fluctuations, especially in low-temperature environments. Temperature changes have a significant impact on the performance and reliability of flash memory.
闪存存储单元的工作机制主要依赖于隧穿效应，通过在存储单元的浮栅和控制栅之间形成隧穿电流来实现数据的写入和擦除。由于隧穿效应对温度极为敏感，闪存可以被视为一种温度敏感性器件。在低温环境中，隧穿电流会减小，导致势垒高度增加，这直接影响了电子注入存储单元的能力，从而使得阈值电压分布发生漂移。当阈值电压分布发生畸变时，数据读取的准确性会受到影响，增加了读取错误率，进而导致数据损坏和系统性能下降。The working mechanism of flash memory cells mainly relies on the tunneling effect, which realizes data writing and erasing by forming a tunneling current between the floating gate and the control gate of the memory cell. Since the tunneling effect is extremely sensitive to temperature, flash memory can be regarded as a temperature-sensitive device. In a low-temperature environment, the tunneling current will decrease, resulting in an increase in the barrier height, which directly affects the ability of electrons to be injected into the memory cell, causing the threshold voltage distribution to drift. When the threshold voltage distribution is distorted, the accuracy of data reading will be affected, increasing the read error rate, which will lead to data corruption and system performance degradation.
低温环境下的闪存可靠性和性能问题，已成为当前存储技术领域亟待解决的痛点问题。在实际应用中，消费电子设备可能会在极端温度条件下工作，例如在高纬度地区的冬季户外环境、冷链物流监控、航空航天等特殊领域。因此，如何在低温环境下有效提升闪存的可靠性和读取性能成为一个重要的研究方向。Flash memory reliability and performance issues in low-temperature environments have become a pain point that needs to be solved in the current storage technology field. In practical applications, consumer electronic devices may work under extreme temperature conditions, such as in winter outdoor environments in high-latitude areas, cold chain logistics monitoring, aerospace and other special fields. Therefore, how to effectively improve the reliability and read performance of flash memory in low-temperature environments has become an important research direction.
发明内容Summary of the invention
为解决现有技术中尚未公开一种在低温环境下有效提升闪存的可靠性和读取性能的技术方案的缺陷，本发明提供的技术方案为：In order to solve the defect that there is no technical solution disclosed in the prior art that effectively improves the reliability and reading performance of flash memory in a low temperature environment, the technical solution provided by the present invention is:
闪存低温可靠性提升模型建立方法，所述方法包括：A method for establishing a flash memory low temperature reliability improvement model, the method comprising:
采集闪存在不同温度下的阈值电压偏移数据集，并预处理的步骤；The steps of collecting the threshold voltage shift data set of the flash memory at different temperatures and preprocessing it;
根据预处理后的所述阈值电压偏移数据集的数据，得到不同温度与最优读参考电压偏移之间的初步关系模型的步骤；A step of obtaining a preliminary relationship model between different temperatures and an optimal read reference voltage offset according to the preprocessed data of the threshold voltage offset data set;
根据预设的所述闪存的影响因素，对所述初步关系模型进行修正，得到修正模型的步骤；The step of modifying the preliminary relationship model according to the preset influencing factors of the flash memory to obtain a modified model;
根据所述修正模型和所述影响因素，建立综合补偿模型的步骤。The step of establishing a comprehensive compensation model according to the correction model and the influencing factors.
进一步，提供一个优选实施方式，根据所述修正模型和所述影响因素，通过多元回归或机器学习方法建立综合补偿模型。Furthermore, a preferred implementation is provided, in which a comprehensive compensation model is established by a multivariate regression or machine learning method based on the correction model and the influencing factors.
进一步，提供一个优选实施方式，所述影响因素包括不同温度、所述闪存所在层位置和P/E磨损因素。Furthermore, a preferred embodiment is provided, wherein the influencing factors include different temperatures, the layer location of the flash memory, and P/E wear factors.
进一步，提供一个优选实施方式，通过线性回归或多项式回归方法对预处理后的所述阈值电压偏移数据集的数据进行初步拟合，得到所述初步关系模型。Furthermore, a preferred embodiment is provided, in which a preliminary fitting is performed on the preprocessed data of the threshold voltage shift data set by a linear regression or polynomial regression method to obtain the preliminary relationship model.
基于同一发明构思，本发明还提供了闪存低温可靠性提升模型建立装置，所述装置包括：Based on the same inventive concept, the present invention also provides a flash memory low temperature reliability improvement model establishment device, the device comprising:
采集闪存在不同温度下的阈值电压偏移数据集，并预处理的模块；A module that collects and preprocesses the threshold voltage shift data set of flash memory at different temperatures;
根据预处理后的所述阈值电压偏移数据集的数据，得到不同温度与最优读参考电压偏移之间的初步关系模型的模块；A module for obtaining a preliminary relationship model between different temperatures and an optimal read reference voltage offset according to the preprocessed data of the threshold voltage offset data set;
根据预设的所述闪存的影响因素，对所述初步关系模型进行修正，得到修正模型的模块；According to the preset influencing factors of the flash memory, the preliminary relationship model is modified to obtain a module of the modified model;
根据所述修正模型和所述影响因素，建立综合补偿模型的模块。A module of a comprehensive compensation model is established based on the correction model and the influencing factors.
基于同一发明构思，本发明还提供了一种基于读参考电压校准的3-D闪存低温可靠性和读取性能提升方法，所述方法包括：Based on the same inventive concept, the present invention also provides a method for improving low-temperature reliability and read performance of a 3-D flash memory based on read reference voltage calibration, the method comprising:
采集闪存样本的步骤；Steps to collect flash memory samples;
将所述闪存样本在不同温度下编程，并记录所述闪存样本在不同温度下的阈值电压偏移数据集的步骤；The step of programming the flash memory sample at different temperatures and recording the threshold voltage shift data sets of the flash memory sample at different temperatures;
建立所述闪存样本在不同温度下，最优读参考电压偏移系数关系曲线的步骤；The step of establishing an optimal read reference voltage offset coefficient relationship curve of the flash memory sample at different temperatures;
通过所述的方法建立的模型，对所述阈值电压偏移数据集和最优读参考电压偏移系数关系曲线进行处理，得到补偿数据的步骤。The model established by the method described above is used to process the threshold voltage offset data set and the optimal read reference voltage offset coefficient relationship curve to obtain compensation data.
基于同一发明构思，本发明还提供了一种基于读参考电压校准的3-D闪存低温可靠性和读取性能提升装置，所述装置包括：Based on the same inventive concept, the present invention also provides a device for improving low temperature reliability and read performance of a 3-D flash memory based on read reference voltage calibration, the device comprising:
采集闪存样本的模块；Module for collecting flash memory samples;
将所述闪存样本在不同温度下编程，并记录所述闪存样本在不同温度下的阈值电压偏移数据集的模块；A module for programming the flash memory sample at different temperatures and recording a threshold voltage shift data set of the flash memory sample at different temperatures;
建立所述闪存样本在不同温度下，最优读参考电压偏移系数关系曲线的模块；A module for establishing a relationship curve of an optimal read reference voltage offset coefficient of the flash memory sample at different temperatures;
通过所述的装置建立的模型，对所述阈值电压偏移数据集和最优读参考电压偏移系数关系曲线进行处理，得到补偿数据的模块。The model established by the device is used to process the threshold voltage offset data set and the optimal read reference voltage offset coefficient relationship curve to obtain a compensation data module.
基于同一发明构思，本发明还提供了计算机储存介质，用于储存计算机程序，当所述计算机程序被计算机读取时，实现所述的方法。Based on the same inventive concept, the present invention also provides a computer storage medium for storing a computer program, and when the computer program is read by a computer, the method described is implemented.
基于同一发明构思，本发明还提供了计算机，包括处理器和储存介质，当所述储存介质中储存的计算机程序被所述处理器读取时，实现所述的方法。Based on the same inventive concept, the present invention also provides a computer, including a processor and a storage medium, and when the computer program stored in the storage medium is read by the processor, the described method is implemented.
基于同一发明构思，本发明还提供了计算机程序产品，嵌入有计算机程序，当所述计算机程序被处理器读取时，实现所述的方法。Based on the same inventive concept, the present invention also provides a computer program product, which is embedded with a computer program. When the computer program is read by a processor, the method described above is implemented.
与现有技术相比，本发明提供的技术方案的有益之处在于：Compared with the prior art, the technical solution provided by the present invention is beneficial in that:
本发明提供的一种基于读参考电压校准的3-D闪存低温可靠性和读取性能提升方法，通过对闪存样本进行预处理和设计合理的测试方案，确保了实验能够覆盖不同生命周期阶段和工作温度范围。这种方式确保了实验数据的全面性和可靠性，从而为后续的数据分析提供了可靠的基础。The present invention provides a method for improving the low-temperature reliability and reading performance of 3-D flash memory based on read reference voltage calibration. By preprocessing flash memory samples and designing a reasonable test plan, it ensures that the experiment can cover different life cycle stages and operating temperature ranges. This method ensures the comprehensiveness and reliability of experimental data, thereby providing a reliable basis for subsequent data analysis.
本发明提供的一种基于读参考电压校准的3-D闪存低温可靠性和读取性能提升方法，通过实验数据与理论分析的比对，确定了低温对闪存编程的抑制作用，并提出了编程温度影响量化分析方法。这种方法使得能够量化不同编程温度对阈值电压分布的影响，为后续建立补偿模型提供了必要的数据支持。The present invention provides a method for improving the low temperature reliability and reading performance of 3-D flash memory based on read reference voltage calibration. By comparing experimental data with theoretical analysis, the inhibitory effect of low temperature on flash memory programming is determined, and a quantitative analysis method for the influence of programming temperature is proposed. This method enables the quantification of the influence of different programming temperatures on the threshold voltage distribution, providing the necessary data support for the subsequent establishment of a compensation model.
本发明提供的一种基于读参考电压校准的3-D闪存低温可靠性和读取性能提升方法，基于实验数据，构建了编程温度与最优读参考电压之间的转换模型。该模型综合考虑了不同层位置、单元状态和P/E周期对低温编程可靠性的影响，从而提高了温度补偿的精度和准确性。The present invention provides a method for improving the low temperature reliability and read performance of 3-D flash memory based on read reference voltage calibration. Based on experimental data, a conversion model between programming temperature and optimal read reference voltage is constructed. The model comprehensively considers the influence of different layer positions, cell states and P/E cycles on low temperature programming reliability, thereby improving the precision and accuracy of temperature compensation.
本发明提供的一种基于读参考电压校准的3-D闪存低温可靠性和读取性能提升方法，通过与现有的先进温度补偿策略进行比较，验证了本发明策略在减少读取重试次数方面的性能优势。实验结果表明，本方法在缓解低温编程引起的可靠性问题上表现出色，平均降低了原始误码率，并且在闪存读取性能优化方面也表现出更好的效果。The present invention provides a method for improving the low-temperature reliability and read performance of 3-D flash memory based on read reference voltage calibration. By comparing with the existing advanced temperature compensation strategy, the performance advantage of the present invention strategy in reducing the number of read retries is verified. The experimental results show that the present method performs well in alleviating the reliability problems caused by low-temperature programming, reduces the original bit error rate on average, and also shows better results in optimizing the read performance of flash memory.
本发明提供的一种基于读参考电压校准的3-D闪存低温可靠性和读取性能提升方法，基于读参考电压校准的方法充分考虑了闪存在低温环境下的特性，通过细致的实验设计和数据分析，建立了更加精准的补偿模型，从而在提升闪存低温可靠性和读取性能方面取得了显著的效果。The present invention provides a method for improving the low-temperature reliability and reading performance of 3-D flash memory based on read reference voltage calibration. The method based on read reference voltage calibration fully considers the characteristics of flash memory in a low-temperature environment, and establishes a more accurate compensation model through meticulous experimental design and data analysis, thereby achieving remarkable results in improving the low-temperature reliability and reading performance of flash memory.
本发明提供的一种基于读参考电压校准的3-D闪存低温可靠性和读取性能提升方法，适合应用于NAND Flash的读参考电压校准的工作中。The present invention provides a method for improving low-temperature reliability and reading performance of a 3-D flash memory based on read reference voltage calibration, which is suitable for application in the work of NAND Flash read reference voltage calibration.
附图说明BRIEF DESCRIPTION OF THE DRAWINGS
图1为不同编程温度实验组分别在20℃环境下读取的阈值电压分布曲线对比；FIG1 is a comparison of threshold voltage distribution curves read at 20°C for different programming temperature experimental groups;
图2为编程温度变化时不同RRV的偏移量对比；Figure 2 is a comparison of the offsets of different RRVs when programming temperature changes;
图3为不同编程温度下3-D NAND闪存不同层的最优RRV偏移对比；FIG3 is a comparison of the optimal RRV offsets of different layers of 3-D NAND flash memory at different programming temperatures;
图4为不同P/E磨损闪存的高低温编程最优RRV偏移曲线比较；FIG4 is a comparison of the optimal RRV offset curves for high and low temperature programming of flash memories with different P/E wear;
图5为3-D NAND闪存不同层的线性拟合R2指标对比；Figure 5 is a comparison of the linear fitting R 2 index of different layers of 3-D NAND flash memory;
图6温度补偿策略基本流程；Figure 6 Basic flow of temperature compensation strategy;
图7为寿命末期闪存的RBER分布曲线；FIG7 is a RBER distribution curve of a flash memory at the end of its life;
图8为编程温度变化时采用不同补偿策略的闪存块平均重读次数比较。FIG8 compares the average reread times of flash memory blocks using different compensation strategies when the programming temperature changes.
具体实施方式DETAILED DESCRIPTION
为使本发明提供的技术方案的优点和有益之处体现得更清楚，现结合附图对本发明提供的技术方案进行进一步详细地描述，具体的：In order to make the advantages and benefits of the technical solution provided by the present invention more clearly reflected, the technical solution provided by the present invention is now further described in detail with reference to the accompanying drawings, specifically:
实施方式一、本实施方式提供了闪存低温可靠性提升模型建立方法，所述方法包括：Embodiment 1: This embodiment provides a method for establishing a flash memory low temperature reliability improvement model, the method comprising:
采集闪存在不同温度下的阈值电压偏移数据集，并预处理的步骤；The steps of collecting the threshold voltage shift data set of the flash memory at different temperatures and preprocessing it;
根据预处理后的所述阈值电压偏移数据集的数据，得到不同温度与最优读参考电压偏移之间的初步关系模型的步骤；A step of obtaining a preliminary relationship model between different temperatures and an optimal read reference voltage offset according to the preprocessed data of the threshold voltage offset data set;
根据预设的所述闪存的影响因素，对所述初步关系模型进行修正，得到修正模型的步骤；The step of modifying the preliminary relationship model according to the preset influencing factors of the flash memory to obtain a modified model;
根据所述修正模型和所述影响因素，建立综合补偿模型的步骤。The step of establishing a comprehensive compensation model according to the correction model and the influencing factors.
实施方式二、本实施方式是对实施方式一提供的闪存低温可靠性提升模型建立方法的进一步限定，根据所述修正模型和所述影响因素，通过多元回归或机器学习方法建立综合补偿模型。Implementation method 2: This implementation method further limits the method for establishing a flash memory low-temperature reliability improvement model provided in implementation method 1. According to the correction model and the influencing factors, a comprehensive compensation model is established through multivariate regression or machine learning methods.
实施方式三、本实施方式是对实施方式一提供的闪存低温可靠性提升模型建立方法的进一步限定，所述影响因素包括不同温度、所述闪存所在层位置和P/E磨损因素。Implementation method three: This implementation method further limits the method for establishing a flash memory low-temperature reliability improvement model provided in implementation method one, and the influencing factors include different temperatures, the layer position of the flash memory, and P/E wear factors.
实施方式四、本实施方式是对实施方式一提供的闪存低温可靠性提升模型建立方法的进一步限定，通过线性回归或多项式回归方法对预处理后的所述阈值电压偏移数据集的数据进行初步拟合，得到所述初步关系模型。Implementation method 4: This implementation method further limits the method for establishing a flash memory low-temperature reliability improvement model provided in implementation method 1. The preliminary relationship model is obtained by performing a preliminary fitting on the preprocessed data of the threshold voltage offset data set through a linear regression or polynomial regression method.
实施方式五、本实施方式提供了闪存低温可靠性提升模型建立装置，所述装置包括：Embodiment 5: This embodiment provides a flash memory low temperature reliability improvement model establishment device, the device comprising:
采集闪存在不同温度下的阈值电压偏移数据集，并预处理的模块；A module that collects and preprocesses the threshold voltage shift data set of flash memory at different temperatures;
根据预处理后的所述阈值电压偏移数据集的数据，得到不同温度与最优读参考电压偏移之间的初步关系模型的模块；A module for obtaining a preliminary relationship model between different temperatures and an optimal read reference voltage offset according to the preprocessed data of the threshold voltage offset data set;
根据预设的所述闪存的影响因素，对所述初步关系模型进行修正，得到修正模型的模块；According to the preset influencing factors of the flash memory, the preliminary relationship model is modified to obtain a module of the modified model;
根据所述修正模型和所述影响因素，建立综合补偿模型的模块。A module of a comprehensive compensation model is established based on the correction model and the influencing factors.
实施方式六、本实施方式提供了一种基于读参考电压校准的3-D闪存低温可靠性和读取性能提升方法，所述方法包括：Embodiment 6: This embodiment provides a method for improving low temperature reliability and read performance of a 3-D flash memory based on read reference voltage calibration, the method comprising:
采集闪存样本的步骤；Steps to collect flash memory samples;
将所述闪存样本在不同温度下编程，并记录所述闪存样本在不同温度下的阈值电压偏移数据集的步骤；The step of programming the flash memory sample at different temperatures and recording the threshold voltage shift data sets of the flash memory sample at different temperatures;
建立所述闪存样本在不同温度下，最优读参考电压偏移系数关系曲线的步骤；The step of establishing an optimal read reference voltage offset coefficient relationship curve of the flash memory sample at different temperatures;
通过实施方式一提供的方法建立的模型，对所述阈值电压偏移数据集和最优读参考电压偏移系数关系曲线进行处理，得到补偿数据的步骤。The model established by the method provided in the first embodiment is used to process the threshold voltage offset data set and the optimal read reference voltage offset coefficient relationship curve to obtain compensation data.
具体的，本实施方式提供的技术方案，提出了一种基于读参考电压校准的3-D闪存低温可靠性提升方法。该方法通过量化不同编程温度下的读参考电压偏移数据，构建编程温度与最优读参考电压之间的转换模型，从而补偿低温编程对闪存性能的影响，提高低温环境下闪存的可靠性和读取性能。Specifically, the technical solution provided in this embodiment proposes a method for improving the low-temperature reliability of 3-D flash memory based on read reference voltage calibration. This method quantifies the read reference voltage offset data at different programming temperatures and constructs a conversion model between programming temperature and optimal read reference voltage, thereby compensating for the impact of low-temperature programming on flash memory performance and improving the reliability and read performance of flash memory in low-temperature environments.
1.数据预处理1. Data preprocessing
输入：预处理后的闪存样本Input: Preprocessed flash sample
目的：覆盖闪存不同生命周期阶段的测试样本Purpose: To cover test samples at different life cycle stages of flash memory
步骤：对闪存样本进行预编程和擦除处理，确保测试样本能够覆盖闪存的不同生命周期阶段。Steps: Pre-program and erase the flash memory samples to ensure that the test samples can cover different life cycle stages of the flash memory.
2.测试方案设计2. Test plan design
输入：预处理后的测试样本Input: preprocessed test sample
目的：不同编程温度下的阈值电压分布数据Purpose: Threshold voltage distribution data at different programming temperatures
步骤：根据校准对象的工作温度进行实验设计，分为编程、驻留和读取三个阶段。将样品分别在不同温度下编程，并记录各组闪存的阈值电压分布数据。Steps: Design the experiment according to the working temperature of the calibration object, which is divided into three stages: programming, dwelling and reading. Program the samples at different temperatures and record the threshold voltage distribution data of each group of flash memory.
3.温度特性测试与数据分析3. Temperature characteristics test and data analysis
输入：不同编程温度下的阈值电压分布数据Input: Threshold voltage distribution data at different programming temperatures
目的：编程温度对阈值电压分布的影响分析结果Purpose: Analysis of the effect of programming temperature on threshold voltage distribution
步骤：使用闪存算法验证平台测试不同编程温度下的阈值电压分布数据，分析低温对闪存编程的抑制作用及其对阈值电压分布的影响。Steps: Use the flash algorithm verification platform to test the threshold voltage distribution data at different programming temperatures, and analyze the inhibitory effect of low temperature on flash programming and its impact on the threshold voltage distribution.
4.编程温度影响量化分析4. Quantitative analysis of programming temperature impact
输入：温度特性测试数据Input: Temperature characteristic test data
目的：最优读参考电压偏移系数与编程温度关系曲线Purpose: Optimal read reference voltage offset coefficient vs. programming temperature curve
步骤：绘制不同编程温度下的最优读参考电压偏移系数关系曲线，分析不同读参考电压在不同编程温度下的偏移量。Steps: Draw the optimal read reference voltage offset coefficient relationship curve at different programming temperatures, and analyze the offset of different read reference voltages at different programming temperatures.
5.干扰因素研究5. Research on interference factors
输入：编程温度影响量化数据Input: Quantitative data on programming temperature effects
目的：考虑层位置、P/E磨损等因素的温度补偿模型参数Purpose: Temperature compensation model parameters considering factors such as layer position, P/E wear, etc.
步骤：研究3-D闪存层位置和P/E磨损等因素对编程温度与最优读参考电压偏移系数关系的影响。Steps: Study the effects of factors such as 3-D flash memory layer position and P/E wear on the relationship between programming temperature and optimal read reference voltage offset coefficient.
6.建立补偿模型6. Build a compensation model
输入：温度特性测试与数据分析结果Input: Temperature characteristics test and data analysis results
目的：编程温度与最优读参考电压之间的转换模型Purpose: Conversion model between programming temperature and optimal read reference voltage
步骤：基于实验数据构建编程温度与最优读参考电压之间的转换模型，考虑不同层位置、单元状态和P/E周期对低温编程可靠性的影响。Steps: Construct a conversion model between programming temperature and optimal read reference voltage based on experimental data, considering the impact of different layer positions, cell states and P/E cycles on low-temperature programming reliability.
7.拟合精度分析7. Fitting accuracy analysis
输入：补偿模型Input: Compensation Model
目的：线性拟合的R-square参数评估结果Purpose: R-square parameter evaluation results of linear fit
步骤：使用线性函数拟合不同编程温度下的读参考电压偏移量，并通过R-square参数评估拟合的准确性。Steps: Use a linear function to fit the read reference voltage offset at different programming temperatures and evaluate the accuracy of the fit using the R-square parameter.
8.温度补偿策略实施8. Temperature compensation strategy implementation
输入：补偿模型参数Input: Compensation model parameters
目的：优化后的读参考电压校准方案Purpose: Optimized read reference voltage calibration scheme
步骤：在闪存读取过程中应用补偿模型，以补偿温度变化引起的闪存阈值电压分布畸变，提高低温环境下的读取性能。Steps: Apply the compensation model during the flash memory reading process to compensate for the flash memory threshold voltage distribution distortion caused by temperature changes and improve the reading performance in low temperature environments.
9.性能验证9. Performance Verification
输入：优化后的读参考电压校准方案Input: Optimized read reference voltage calibration scheme
目的：闪存读取性能和可靠性的实验数据Purpose: Experimental data on flash memory read performance and reliability
步骤：通过与现有的温度补偿策略进行比较，验证本发明在减少读取重试次数和降低原始误码率方面的性能优势。Steps: By comparing with the existing temperature compensation strategy, the performance advantages of the present invention in reducing the number of read retries and lowering the original bit error rate are verified.
该技术方案通过多步骤的实验和数据分析，建立了一个考虑多种因素的编程温度补偿模型，最终提高了3-D闪存在低温环境下的可靠性和读取性能。此方案不仅在技术上具有创新性，还在实践中显示出显著的性能提升效果。Through multi-step experiments and data analysis, this technical solution established a programming temperature compensation model that takes into account multiple factors, ultimately improving the reliability and reading performance of 3-D flash memory in low temperature environments. This solution is not only technologically innovative, but also shows significant performance improvement effects in practice.
具体的，步骤6包括：Specifically, step 6 includes:
收集实验数据Collecting experimental data
输入：不同编程温度下的阈值电压分布数据Input: Threshold voltage distribution data at different programming temperatures
目的：编程温度与对应的最优读参考电压偏移数据集Purpose: Programming temperature and corresponding optimal read reference voltage offset data set
步骤：从温度特性测试与数据分析中提取不同编程温度下的阈值电压分布数据，计算出每个温度对应的最优读参考电压偏移量，形成数据集。Steps: Extract threshold voltage distribution data at different programming temperatures from temperature characteristic testing and data analysis, calculate the optimal read reference voltage offset corresponding to each temperature, and form a data set.
数据清洗与预处理Data cleaning and preprocessing
输入：编程温度与最优读参考电压偏移数据集Input: Programming temperature and optimal read reference voltage offset data set
目的：清洗后的有效数据集Purpose: Valid data set after cleaning
步骤：对收集到的数据进行清洗，去除异常值和噪声，确保数据的准确性和可靠性，得到有效的数据集。Steps: Clean the collected data, remove outliers and noise, ensure the accuracy and reliability of the data, and obtain a valid data set.
初步拟合模型Preliminary model fitting
输入：清洗后的有效数据集Input: Valid data set after cleaning
目的：初步拟合的编程温度与读参考电压偏移模型Purpose: Preliminary fitting of programming temperature and read reference voltage offset model
步骤：使用线性回归或多项式回归方法对清洗后的数据进行初步拟合，得到编程温度与最优读参考电压偏移之间的初步关系模型。Steps: Use linear regression or polynomial regression method to perform preliminary fitting on the cleaned data to obtain a preliminary relationship model between programming temperature and optimal read reference voltage offset.
验证拟合精度Verify the fitting accuracy
输入：初步拟合的模型Input: Preliminary fitted model
目的：拟合精度评估结果(如R-square值)Purpose: Fitting accuracy evaluation results (such as R-square value)
步骤：通过计算R-square值等指标来评估初步拟合模型的准确性，确保模型能够较好地反映数据的实际分布。Steps: Evaluate the accuracy of the preliminary fitting model by calculating indicators such as the R-square value to ensure that the model can better reflect the actual distribution of the data.
研究层位置与P/E磨损的影响Study on the influence of layer position and P/E wear
输入：初步拟合的模型，层位置与P/E磨损数据Input: Preliminary fitted model, layer position and P/E wear data
目的：考虑层位置与P/E磨损因素的修正模型Purpose: Modified model considering layer position and P/E wear factors
步骤：引入3-D闪存的层位置和P/E磨损等影响因素，对初步拟合的模型进行修正，构建包含这些因素的更精确的模型。Steps: Introduce influencing factors such as layer position and P/E wear of 3-D flash memory, correct the preliminary fitting model, and build a more accurate model that includes these factors.
构建综合补偿模型Building a comprehensive compensation model
输入：修正后的模型和所有影响因素数据Input: The corrected model and all influencing factors data
目的：综合补偿模型Purpose: Comprehensive compensation model
步骤：综合考虑编程温度、层位置、P/E磨损等多个因素，使用多元回归或机器学习方法构建综合补偿模型，确保模型能够全面反映实际情况。Steps: Consider multiple factors such as programming temperature, layer position, P/E wear, etc., and use multivariate regression or machine learning methods to build a comprehensive compensation model to ensure that the model can fully reflect the actual situation.
模型验证与调整Model validation and tuning
输入：综合补偿模型Input: Comprehensive compensation model
目的：验证后的最终补偿模型Purpose: Final compensation model after verification
步骤：使用独立的数据集对综合补偿模型进行验证，根据验证结果对模型进行必要的调整和优化，确保模型的可靠性和准确性。Steps: Use an independent data set to verify the comprehensive compensation model, and make necessary adjustments and optimizations to the model based on the verification results to ensure the reliability and accuracy of the model.
模型固化与实施Model solidification and implementation
输入：验证后的最终补偿模型Input: Final compensation model after verification
目的：固化的补偿模型参数Purpose: Solidify compensation model parameters
步骤：将最终的补偿模型参数固化，形成可在实际闪存读取过程中应用的校准方案，为低温环境下的读取操作提供有效的补偿机制。Step: Solidify the final compensation model parameters to form a calibration scheme that can be applied in the actual flash memory reading process, providing an effective compensation mechanism for the reading operation in a low temperature environment.
实施方式七、本实施方式提供了一种基于读参考电压校准的3-D闪存低温可靠性和读取性能提升装置，所述装置包括：Embodiment 7: This embodiment provides a device for improving low-temperature reliability and read performance of a 3-D flash memory based on read reference voltage calibration, the device comprising:
采集闪存样本的模块；Module for collecting flash memory samples;
将所述闪存样本在不同温度下编程，并记录所述闪存样本在不同温度下的阈值电压偏移数据集的模块；A module for programming the flash memory sample at different temperatures and recording a threshold voltage shift data set of the flash memory sample at different temperatures;
建立所述闪存样本在不同温度下，最优读参考电压偏移系数关系曲线的模块；A module for establishing a relationship curve of an optimal read reference voltage offset coefficient of the flash memory sample at different temperatures;
通过实施方式五提供的装置建立的模型，对所述阈值电压偏移数据集和最优读参考电压偏移系数关系曲线进行处理，得到补偿数据的模块。The model established by the device provided in the fifth embodiment is used to process the threshold voltage offset data set and the optimal read reference voltage offset coefficient relationship curve to obtain a compensation data module.
实施方式八、本实施方式提供了计算机储存介质，用于储存计算机程序，当所述计算机程序被计算机读取时，实现实施方式一提供的方法。Embodiment 8: This embodiment provides a computer storage medium for storing a computer program. When the computer program is read by a computer, the method provided in embodiment 1 is implemented.
实施方式九、本实施方式提供了计算机，包括处理器和储存介质，当所述储存介质中储存的计算机程序被所述处理器读取时，实现实施方式一提供的方法。Embodiment 9: This embodiment provides a computer, including a processor and a storage medium. When a computer program stored in the storage medium is read by the processor, the method provided in embodiment 1 is implemented.
实施方式十、本实施方式提供了计算机程序产品，嵌入有计算机程序，当所述计算机程序被处理器读取时，实现实施方式一提供的方法。Embodiment 10: This embodiment provides a computer program product, which is embedded with a computer program. When the computer program is read by a processor, the method provided in embodiment 1 is implemented.
实施方式十一、结合图1-8说明本实施方式，本实施方式通过具体实施例，对上述提供的技术方案进行进一步详细地描述，具体的：Embodiment 11: This embodiment is described in conjunction with FIGS. 1-8. This embodiment further describes the technical solution provided above in detail through specific examples, specifically:
本实施方式涉及固态存储领域中，一种NAND Flash的读参考电压校准方法，尤其是涉及一种针对低温环境下提高3-D NAND闪存可靠性和读取性能的方法。在低温环境下闪存可靠性和读取性能会显著下降，这是由于闪存存储技术依赖于隧穿效应在浮栅晶体管中注入和释放电子，从而控制存储单元的阈值电压大小。温度变化对隧穿过程中的势垒高度有显著影响，当温度下降时，隧穿势垒随之升高，增加了向浮栅晶体管中注入电子的难度，导致闪存阈值电压分布出现低温畸变，最终导致读取错误发生。读取错误会降低闪存一次读取成功率，增加闪存控制器纠错的计算开销，因而低温也会影响闪存性能。目前对闪存低温可靠性和性能的综合优化是一个待研究的热点。The present embodiment relates to a method for calibrating a read reference voltage of a NAND Flash in the field of solid-state storage, and more particularly to a method for improving the reliability and read performance of 3-D NAND flash memory in a low-temperature environment. In a low-temperature environment, the reliability and read performance of flash memory will be significantly reduced. This is because flash memory storage technology relies on the tunneling effect to inject and release electrons in floating-gate transistors, thereby controlling the threshold voltage of the storage unit. Temperature changes have a significant impact on the barrier height during the tunneling process. When the temperature drops, the tunneling barrier increases, which increases the difficulty of injecting electrons into the floating-gate transistor, resulting in low-temperature distortion of the flash threshold voltage distribution, and ultimately leading to read errors. Read errors will reduce the success rate of a flash memory read and increase the computational overhead of the flash memory controller for error correction, so low temperatures will also affect the performance of the flash memory. Currently, the comprehensive optimization of the low-temperature reliability and performance of flash memory is a hot topic to be studied.
本实施方式涉及一种3-D闪存低温可靠性和读取性能提升方法，该方法通过量化表征闪存编程温度与最优读参考电压偏移关系，拟合出准确的读参考电压随编程温度变化的偏移模型，进一步实现闪存温度漂移补偿，从而提高低温环境下闪存可靠性和读取性能。The present embodiment relates to a method for improving the low-temperature reliability and read performance of a 3-D flash memory. The method quantitatively characterizes the relationship between the flash memory programming temperature and the optimal read reference voltage offset, fits an accurate offset model of the read reference voltage changing with the programming temperature, and further realizes flash memory temperature drift compensation, thereby improving the flash memory reliability and read performance in a low-temperature environment.
包括：include:
数据预处理：对闪存样本进行预编程/擦除处理，确保测试样本能够覆盖闪存的不同生命周期阶段。Data preprocessing: Pre-program/erase the flash memory samples to ensure that the test samples can cover different life cycle stages of the flash memory.
测试方案设计：需要根据校准对象的工作温度进行实验设计，重点需要关注校准对象的工作温度范围，要求实验温度在工作范围之内。以工业级闪存芯片为例，其工作温度范围是-40℃～65℃。测试分为编程、驻留和读取三个阶段。首先将经过预处理的测试样品根据编程温度被分为三组，每组由4*200个闪存块组成。这些样品分别在20℃、-30℃和60℃的特定温度下编程，每个实验组都写入相同的伪随机序列。其次，所有三组样品在室温下进行60℃的驻留。最后，分别在20℃、-30℃和60℃的温度条件下读取数据，并统计各组闪存的阈值电压分布数据。Test plan design: The experimental design needs to be carried out according to the working temperature of the calibration object, and the focus needs to be on the working temperature range of the calibration object, and the experimental temperature is required to be within the working range. Taking industrial-grade flash memory chips as an example, their operating temperature range is -40℃～65℃. The test is divided into three stages: programming, residence and reading. First, the pre-processed test samples are divided into three groups according to the programming temperature, and each group consists of 4*200 flash memory blocks. These samples are programmed at specific temperatures of 20℃, -30℃ and 60℃, and the same pseudo-random sequence is written to each experimental group. Secondly, all three groups of samples are retained at 60℃ at room temperature. Finally, the data is read at temperatures of 20℃, -30℃ and 60℃, and the threshold voltage distribution data of each group of flash memory is counted.
温度特性测试与数据分析：使用闪存算法验证平台对3-D TLC NAND闪存进行测试，重点关注不同编程温度下的阈值电压分布数据(参见图1)。Temperature characteristic testing and data analysis: The 3-D TLC NAND flash memory is tested using the flash algorithm verification platform, focusing on the threshold voltage distribution data at different programming temperatures (see Figure 1).
实验数据与理论分析的结果相同，低温对闪存编程具有抑制作用，最终编程温度下降和闪存阈值电压分布整体下降(左偏)。The experimental data are consistent with the results of theoretical analysis. Low temperature has an inhibitory effect on flash memory programming, and eventually the programming temperature decreases and the overall distribution of flash memory threshold voltage decreases (left-biased).
编程温度影响量化分析：分析不同编程温度对阈值电压分布的具体影响，绘制最优读参考电压偏移系数与编程温度关系曲线(参见图2)。Quantitative analysis of programming temperature impact: Analyze the specific impact of different programming temperatures on threshold voltage distribution, and draw a curve of the relationship between the optimal read reference voltage offset coefficient and programming temperature (see Figure 2).
图2详细展示了TLC闪存中除Va以外的其他六个读参考电压在不同编程温度条件下的偏移系数。由于Va的读取冗余度显著高于其他读参考电压，并且擦除态与P1态之间的区分度非常高，几乎不存在重叠区域，因此不将Va纳入考虑。分析图2可以得出三个结论：首先，在低温环境下进行编程会导致所有最优RRV值显著降低，RRV校准系数的偏移程度与编程温度之间存在线性相关性。其次，不同RRV之间的偏移量差异在低温编程时尤为显著，最大差异可达近16个偏移单位。最后，不同RRV对编程温度的敏感程度各异，这一点根据它们各自的偏移曲线斜率判断。Figure 2 shows in detail the offset coefficients of the other six read reference voltages except Va in TLC flash memory under different programming temperature conditions. Since the read redundancy of Va is significantly higher than that of other read reference voltages, and the distinction between the erased state and the P1 state is very high, with almost no overlapping area, Va is not taken into consideration. Analysis of Figure 2 can lead to three conclusions: First, programming in a low-temperature environment will cause all optimal RRV values to be significantly reduced, and there is a linear correlation between the offset degree of the RRV calibration coefficient and the programming temperature. Second, the offset difference between different RRVs is particularly significant during low-temperature programming, and the maximum difference can reach nearly 16 offset units. Finally, different RRVs have different sensitivities to programming temperature, which can be judged by the slopes of their respective offset curves.
探究模型其他干扰因素的部分：即研究层位置、P/E磨损等因素是否影响编程温度和最优读参考电压偏移系数之间的数学量化。首先需要研究3-D闪存层位置对模型构造的影响，图3对比了不同层的最优RRV偏移和编程温度曲线。Exploring other interference factors of the model: that is, studying whether factors such as layer position and P/E wear affect the mathematical quantification between programming temperature and optimal read reference voltage offset coefficient. First, it is necessary to study the impact of 3-D flash memory layer position on model construction. Figure 3 compares the optimal RRV offset and programming temperature curves of different layers.
图3以闪存字线编号作为横轴，纵轴为最佳RRV偏移水平。通过分析图3中的数据，观察到不同层位置的最佳RRV偏移呈现出显著的层间差异。在编程过程中，当设定的最大温差达到90℃时，初始层的RRV偏移相对较低，其平均偏移量大约为12.7个偏移单位。相对地，末层的RRV偏移则更为显著，其平均偏移量达到了20.9个偏移单位。Figure 3 uses the flash word line number as the horizontal axis and the vertical axis as the optimal RRV offset level. By analyzing the data in Figure 3, it is observed that the optimal RRV offset at different layer positions shows significant inter-layer differences. During the programming process, when the set maximum temperature difference reaches 90°C, the RRV offset of the initial layer is relatively low, with an average offset of approximately 12.7 offset units. In contrast, the RRV offset of the last layer is more significant, with an average offset of 20.9 offset units.
因此，后续构造编程温度补偿模型时，必须细致考虑不同闪存层之间的性能差异。Therefore, when constructing the programming temperature compensation model later, the performance differences between different flash memory layers must be carefully considered.
图4分析了P/E磨损对构造温度补偿模型的影响。Figure 4 analyzes the effect of P/E wear on the constructed temperature compensation model.
在60℃的编程温度条件下，观察到不同寿命阶段的闪存在最佳读取参考电压上表现出高度一致性，平均偏差仅为0.83个偏移单位。然而，在更低的编程温度，如-30℃时，寿命末期的闪存RRV平均比寿命初期的闪存低2.61个偏移单位。这一实验结果揭示了一个重要现象：随着P/E循环次数的增加，即闪存磨损程度加剧，其阈值电压在低温编程时受到的影响更为显著。Under the programming temperature of 60°C, it was observed that the flash memory at different life stages showed high consistency in the optimal read reference voltage, with an average deviation of only 0.83 offset units. However, at lower programming temperatures, such as -30°C, the RRV of the flash memory at the end of life was 2.61 offset units lower than that of the flash memory at the beginning of life. This experimental result reveals an important phenomenon: as the number of P/E cycles increases, that is, the degree of wear of the flash memory increases, its threshold voltage is more significantly affected during low-temperature programming.
得到：编程温度补偿算法中同样应包含与P/E循环次数相关的参数，以便更准确地补偿因P/E磨损引起的低温阈值电压偏移差异。It is found that the programming temperature compensation algorithm should also include parameters related to the number of P/E cycles in order to more accurately compensate for the low-temperature threshold voltage offset difference caused by P/E wear.
综上所述，在对3-D闪存编程温度特性深入测试的基础上，确认了层位置差异、RRV种类的不同以及P/E磨损程度对闪存编程温度特性存在显著影响。在后续构造用于编程温度补偿的RRV校准模型时，应充分考虑上述因素。In summary, based on the in-depth testing of the programming temperature characteristics of 3-D flash memory, it is confirmed that the layer position difference, the different RRV types and the P/E wear degree have a significant impact on the programming temperature characteristics of flash memory. The above factors should be fully considered when constructing the RRV calibration model for programming temperature compensation in the future.
建立补偿模型：基于实验数据，构建编程温度与最优读参考电压之间的转换模型。该模型能够考虑不同层位置、单元状态和P/E周期对低温编程可靠性的影响，如式1所示。Establish compensation model: Based on experimental data, a conversion model between programming temperature and optimal read reference voltage is constructed. This model can consider the impact of different layer positions, cell states and P/E cycles on low temperature programming reliability, as shown in Equation 1.
RRVOL＝a0·Tprog+C1-lookup(N)+b0 (1)RRVOL＝a 0 ·T prog +C 1- lookup(N)+b 0 (1)
其中，RRVOL(RRV offset level)是RRV在不同编程温度下的补偿偏移系数，Tprog是编程温度，C1是P/E磨损补偿表，N为对应的P/E次数。a0和b0是常数，可根据测试数据通过最小二乘法计算得出。Where, RRVOL (RRV offset level) is the compensation offset coefficient of RRV at different programming temperatures, T prog is the programming temperature, C 1 is the P/E wear compensation table, and N is the corresponding P/E number. a 0 and b 0 are constants that can be calculated by the least squares method based on the test data.
拟合精度分析：使用线性函数拟合不同编程温度下的RRV偏移量，并通过R-square参数评估拟合的准确性。实验数据显示线性拟合误差极小，所有RRV的R-square值均大于0.93。如图5所示。Fitting accuracy analysis: A linear function was used to fit the RRV offset at different programming temperatures, and the accuracy of the fit was evaluated by the R-square parameter. The experimental data showed that the linear fitting error was extremely small, and the R-square values of all RRVs were greater than 0.93. See Figure 5.
本实施方式采用了线性函数模型来描述读取参考电压偏移量与编程温度之间的关系。为了评估这一模型拟合的精确性，引入R平方(R2)这一统计指标。R2衡量的是回归模型中自变量对因变量变异解释的程度，其值域介于0到1之间，值越接近1，表示模型的拟合效果越好。实验结果表明，所采用的线性函数模型在拟合RRV偏移量与编程温度的关系上表现出色，误差极小。所有RRV的R2值均超过了0.93，显示出高度的拟合准确性。This embodiment uses a linear function model to describe the relationship between the read reference voltage offset and the programming temperature. In order to evaluate the accuracy of this model fitting, the statistical indicator R square (R 2 ) is introduced. R 2 measures the degree to which the independent variable in the regression model explains the variation of the dependent variable. Its value range is between 0 and 1. The closer the value is to 1, the better the model fits. The experimental results show that the linear function model used performs well in fitting the relationship between the RRV offset and the programming temperature, with extremely small errors. The R 2 values of all RRVs exceeded 0.93, showing a high degree of fitting accuracy.
温度补偿策略实施：本实施方式策略可对编程温度变化引起的闪存阈值电压分布畸变进行补偿。该策略对编程操作的影响较小，只需要在编程后额外记录当前的闪存温度。闪存读取过程中的策略操作流程如图6所示。Temperature compensation strategy implementation: This implementation strategy can compensate for the flash threshold voltage distribution distortion caused by programming temperature changes. This strategy has little impact on the programming operation and only requires additional recording of the current flash temperature after programming. The strategy operation flow during the flash reading process is shown in Figure 6.
性能验证：通过与现有的先进温度补偿策略进行比较，验证本实施方式策略在减少读取重试次数方面的性能优势。首先对比了本实施方式策略对原始误码率的降低作用，如图7所示。Performance Verification: By comparing with the existing advanced temperature compensation strategy, the performance advantage of the strategy of this implementation in reducing the number of read retries is verified. First, the effect of the strategy of this implementation on reducing the original bit error rate is compared, as shown in Figure 7.
图7中数据清晰地显示，本实施方式策略在缓解闪存由于低温编程而引起的可靠性问题方面发挥了显著作用，平均降低低温编程闪存74.4％的原始误码率。The data in FIG. 7 clearly show that the strategy of this embodiment plays a significant role in alleviating the reliability problem of the flash memory caused by low-temperature programming, and reduces the original bit error rate of the low-temperature programmed flash memory by 74.4% on average.
目前先进温度补偿策略和本实施方式策略对闪存读取性能的优化作用，对比指标为闪存块的平均重读次数，如图8所示。The optimization effect of the current advanced temperature compensation strategy and the strategy of this implementation on the flash memory read performance is compared with the average number of reread times of the flash memory block, as shown in FIG8 .
在0℃以下的所有测试样本中，本实施方式表现优于目前先进算法，平均块重读次数分别比主流算法1和主流算法2低83.9％和80.2％。目前的温度补偿算法，未能充分考虑到闪存层间差异对温度可靠性的潜在影响。与之相对，本实施方式策略重点关注并全面表征这一关键因素。因此，在优化效果上更为出色，这不仅提升了基于闪存的固态存储设备的性能，同时也增强了它们在不同温度条件下的可靠性。In all test samples below 0°C, this implementation outperforms the current advanced algorithms, with average block reread times 83.9% and 80.2% lower than mainstream algorithms 1 and 2, respectively. Current temperature compensation algorithms fail to fully consider the potential impact of inter-layer differences in flash memory on temperature reliability. In contrast, this implementation strategy focuses on and fully characterizes this key factor. Therefore, it is more outstanding in optimization effect, which not only improves the performance of flash-based solid-state storage devices, but also enhances their reliability under different temperature conditions.
本实施方式提供的技术方案：The technical solution provided by this implementation is:
提供了一种基于读参考电压校准的编程温度补偿方法，显著提升了闪存低温场景下的可靠性和读取性能。A programming temperature compensation method based on read reference voltage calibration is provided, which significantly improves the reliability and read performance of flash memory in low temperature scenarios.
该方法考虑了P/E磨损、层差异等因素，获得了更高的校准精度。This method takes into account factors such as P/E wear and layer differences, and achieves higher calibration accuracy.
该方法与现有的3-D NAND闪存技术完全兼容，无需对硬件平台进行大规模改动，即可实现对低温环境下闪存性能的优化。This method is fully compatible with existing 3-D NAND flash memory technology and can optimize flash memory performance in low-temperature environments without making large-scale changes to the hardware platform.
该方法通用性强，基于3-D NAND闪存的固有可靠性特性，适用于当前所有类型的3-D NAND Flash。This method is highly versatile and is applicable to all current types of 3-D NAND Flash based on the inherent reliability characteristics of 3-D NAND Flash.
该方法存储开销低，只需要存储编程温度数据和线性拟合模型参数，存储开销相对较低，对整体系统影响小。This method has low storage overhead and only needs to store programming temperature data and linear fitting model parameters. The storage overhead is relatively low and has little impact on the overall system.
该方法的实施流程简洁明了，易于集成到现有的闪存管理系统中，便于推广应用。The implementation process of the method is concise and clear, and it is easy to integrate into the existing flash memory management system, so it is convenient for promotion and application.
以上通过几个具体实施方式对本发明提供的技术方案进行进一步详细地描述，是为了突出本发明提供的技术方案的优点和有益之处，不过以上所述的几个具体实施方式并不用于作为对本发明的限制，任何基于本发明的精神和原则范围内的，对本发明的合理修改和改进、实施方式的组合和等同替换等，均应当包含在本发明的保护范围之内。The technical solution provided by the present invention is further described in detail above through several specific implementation modes in order to highlight the advantages and benefits of the technical solution provided by the present invention. However, the several specific implementation modes described above are not intended to be used as limitations on the present invention. Any reasonable modification and improvement of the present invention, combination of implementation modes and equivalent substitution within the spirit and principle of the present invention shall be included in the protection scope of the present invention.
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