随着栅极长度、硅膜厚度以及埋氧层厚度的减小,MOS器件短沟道效应变得越来越严峻。本文首先给出了决定全耗尽绝缘体上硅短沟道效应的三种机制;然后从接地层、埋层工程、沟道工程、源漏工程、侧墙工程和栅工程等六种工程技术方面讨论了...随着栅极长度、硅膜厚度以及埋氧层厚度的减小,MOS器件短沟道效应变得越来越严峻。本文首先给出了决定全耗尽绝缘体上硅短沟道效应的三种机制;然后从接地层、埋层工程、沟道工程、源漏工程、侧墙工程和栅工程等六种工程技术方面讨论了为抑制短沟道效应而引入的不同UTBB SOI MOSFETs结构,分析了这些结构能够有效抑制短沟道效应(如漏致势垒降低、亚阈值摆幅、关态泄露电流、开态电流等)的机理;而后基于这六种技术,对近年来在UTBB SOI MOSFETs短沟道效应抑制方面所做的工作进行了总结;最后对未来技术的发展进行了展望。展开更多
This is Part II of a two-part paper that explores the 28-nm UTBB FD-SOI CMOS and the 22-nm Tri-Gate FinFET technology as the better alternatives to bulk transistors especially when the transistor’s architecture is go...This is Part II of a two-part paper that explores the 28-nm UTBB FD-SOI CMOS and the 22-nm Tri-Gate FinFET technology as the better alternatives to bulk transistors especially when the transistor’s architecture is going fully depleted and its size is becoming much smaller, 28-nm and above. Reliability tests of those alternatives are first discussed. Then, a comparison is made between the two alternative transistors comparing their physical properties, electrical properties, and their preferences in different applications.展开更多
Nowadays, transistor technology is going toward the fully depleted architecture;the bulk transistors are becoming more complex in manufacturing as the transistor size is becoming smaller to achieve the high performanc...Nowadays, transistor technology is going toward the fully depleted architecture;the bulk transistors are becoming more complex in manufacturing as the transistor size is becoming smaller to achieve the high performance especially at the node 28 nm. This is the first of two papers that discuss the basic drawbacks of the bulk transistors and explain the two alternative transistors: 28 nm UTBB FD-SOI CMOS and the 22 nm Tri-Gate FinFET. The accompanying paper, Part II, focuses on the comparison between those alternatives and their physical properties, electrical properties, and reliability tests to properly set the preferences when choosing for different mobile media and consumers’ applications.展开更多
In this work, the impact of well doping and corresponding body bias on UTBB MOSFETs is investigated. The ability of threshold voltage adjustment is evaluated. The results indicate that well doping can change the thres...In this work, the impact of well doping and corresponding body bias on UTBB MOSFETs is investigated. The ability of threshold voltage adjustment is evaluated. The results indicate that well doping can change the threshold voltage both of the N and P channel UTBB MOSFETs. The maximum amplitude for a typical 26 nm gate length device is about 100 mV, and these correspond to the cases of devices with an inverse type of high concentration dopant. The body bias adjusts the threshold voltage at a rate of 100-140 mV/V for the UTBB MOSFETs with a well. By optimizing well doping and body biasing, multi-threshold-voltage UTBB MOSFETs can be designed and optimized for lower power application.展开更多
MOS bulk transistor is reaching its limits: sub-threshold slope (SS), drain induced barrier lowering (DIBL), threshold voltage (VT) and VDD scaling slowing down, more power dissipation, less speed gain, less ac...MOS bulk transistor is reaching its limits: sub-threshold slope (SS), drain induced barrier lowering (DIBL), threshold voltage (VT) and VDD scaling slowing down, more power dissipation, less speed gain, less accuracy, variability and reliability issues. Fully depleted devices are mandatory to continue the technology roadmap. FDSOI technology relies on a thin layer of silicon that is over a buried oxide (BOx). Called ultra thin body and buried oxide (UTBB) transistor, FDSOI transistors correspond to a simple evolution from conventional MOS bulk transistor. The capability to bias the back-gate allows us to implement calibration techniques without adding transistors in critical blocks. We have illustrated this technique on a very low power voltage-controlled oscillator (VCO) based on a ring oscillator (RO) designed in 28 nm FDSOI technology. Despite the fact that such VCO topology exhibits a larger phase noise, this design will address aggressively the size and power consumption reduction. Indeed we are using the efficient back-gate biasing offered by the FDSOI MOS transistor to compensate the mismatches between the different inverters of the ring oscillator to decrease jitter and phase noise. We will present the reasons which led us to use the FDSOI technology to reach the specifications of this PLL. The VCRO exhibits a 0.8 mW power consumption, with a phase noise about -94 dBc/Hz@l MHz.展开更多
文摘随着栅极长度、硅膜厚度以及埋氧层厚度的减小,MOS器件短沟道效应变得越来越严峻。本文首先给出了决定全耗尽绝缘体上硅短沟道效应的三种机制;然后从接地层、埋层工程、沟道工程、源漏工程、侧墙工程和栅工程等六种工程技术方面讨论了为抑制短沟道效应而引入的不同UTBB SOI MOSFETs结构,分析了这些结构能够有效抑制短沟道效应(如漏致势垒降低、亚阈值摆幅、关态泄露电流、开态电流等)的机理;而后基于这六种技术,对近年来在UTBB SOI MOSFETs短沟道效应抑制方面所做的工作进行了总结;最后对未来技术的发展进行了展望。
文摘This is Part II of a two-part paper that explores the 28-nm UTBB FD-SOI CMOS and the 22-nm Tri-Gate FinFET technology as the better alternatives to bulk transistors especially when the transistor’s architecture is going fully depleted and its size is becoming much smaller, 28-nm and above. Reliability tests of those alternatives are first discussed. Then, a comparison is made between the two alternative transistors comparing their physical properties, electrical properties, and their preferences in different applications.
文摘Nowadays, transistor technology is going toward the fully depleted architecture;the bulk transistors are becoming more complex in manufacturing as the transistor size is becoming smaller to achieve the high performance especially at the node 28 nm. This is the first of two papers that discuss the basic drawbacks of the bulk transistors and explain the two alternative transistors: 28 nm UTBB FD-SOI CMOS and the 22 nm Tri-Gate FinFET. The accompanying paper, Part II, focuses on the comparison between those alternatives and their physical properties, electrical properties, and reliability tests to properly set the preferences when choosing for different mobile media and consumers’ applications.
基金Project supported by the National Key R&D Plan(No.2016YFA0202101)
文摘In this work, the impact of well doping and corresponding body bias on UTBB MOSFETs is investigated. The ability of threshold voltage adjustment is evaluated. The results indicate that well doping can change the threshold voltage both of the N and P channel UTBB MOSFETs. The maximum amplitude for a typical 26 nm gate length device is about 100 mV, and these correspond to the cases of devices with an inverse type of high concentration dopant. The body bias adjusts the threshold voltage at a rate of 100-140 mV/V for the UTBB MOSFETs with a well. By optimizing well doping and body biasing, multi-threshold-voltage UTBB MOSFETs can be designed and optimized for lower power application.
文摘MOS bulk transistor is reaching its limits: sub-threshold slope (SS), drain induced barrier lowering (DIBL), threshold voltage (VT) and VDD scaling slowing down, more power dissipation, less speed gain, less accuracy, variability and reliability issues. Fully depleted devices are mandatory to continue the technology roadmap. FDSOI technology relies on a thin layer of silicon that is over a buried oxide (BOx). Called ultra thin body and buried oxide (UTBB) transistor, FDSOI transistors correspond to a simple evolution from conventional MOS bulk transistor. The capability to bias the back-gate allows us to implement calibration techniques without adding transistors in critical blocks. We have illustrated this technique on a very low power voltage-controlled oscillator (VCO) based on a ring oscillator (RO) designed in 28 nm FDSOI technology. Despite the fact that such VCO topology exhibits a larger phase noise, this design will address aggressively the size and power consumption reduction. Indeed we are using the efficient back-gate biasing offered by the FDSOI MOS transistor to compensate the mismatches between the different inverters of the ring oscillator to decrease jitter and phase noise. We will present the reasons which led us to use the FDSOI technology to reach the specifications of this PLL. The VCRO exhibits a 0.8 mW power consumption, with a phase noise about -94 dBc/Hz@l MHz.