In this paper we propose a new model for leakage mechanism in tailmode bits of dram data retention characteristics. However, gateinduced drain leakage gidl is a major concern at low power technology nodes because of bandtoband and trapassisted tunneling tat due to reduced bandgap. Us7359271b2 gate induced drain leakage current reduction. State independent average gate leakage current of a logic gate 4 1. Gate induced drain leakage gidl is caused by high field effect in the drain junction of mos transistors. Gate induced drain leakage gidl gate induced drain leakage gidl is caused by high field effect in the drain junction of mos transistors. One leakage current mechanism that has been mostly neglected until recently is called the gate induced drain leakage gidl. This paper investigates the effect of the asymmetric source and drain geometries of surround gate vertical mosfets on the drain leakage currents in the offstate region of operation. Pdf enhanced gate induced drain leakage current in hfo2. Gate induce drain leakage gidl is another signi cant leakage mechanism, resulting from the depletion at the drain surface below the gate drain overlap region. The reasons are i the subthreshold conduction increases exponentially due to the threshold voltage reduction. Offstate leakage induced by bandtoband tunneling and. Device design considerations for minimizing the gateinduced drain leakage current are discussed.
Gate induced drain current gidl is a band to band tunneling phenomenon and an offstate leakage current mechanism. Gate induced drain leakage gidl is another significant leakage mechanism, resulting due to the depletion at the drain surface below the gate drain overlap region. Revisited approach for the characterization of gate induced. Gate induced drain leakage current in 45nm cmos technology. Analysis of gateinduced drain leakage mechanisms in silicongermanium channel pfet article pdf available in ieee transactions on electron devices 615. Model of random telegraph noise in gate induced drain leakage current of highk gate dielectric metaloxidesemiconductor fieldeffect transistors appl. Gate induced drain leakage gidl gateinduced drain leakage gidl is caused by high field effect in the drain junction of mos transistors.
Hot carrier effect on gate induced drain leakage current in highkmetal gate nchannel metaloxidesemiconductor fieldeffect transistors chihhao dai,1 tingchang chang,1,2,3,a annkuo chu,1 yuanjui kuo,1 szuhan ho,4 tienyu hsieh,2 wenhung lo,2 chingen chen,4 joumiao shih,2 wanlin chung,2 baishan dai,2 huamao chen,2 guangrui xia,5 osbert cheng,6 and cheng tung huang6. Impact of gate induced drain leakage on overall leakage of. When the gate is biased to form an accumulation layer at the silicon surface, the silicon surface under the gate has almost same potential as the ptype substrate. Modeling of shallow extension engineered dual metal. The root cause is electric field enhancement caused by.
Kobayashi faculty of science and technology, gunma university d33 asicon chengdu 36 november 2015. The incorporation of draininduced barrier lowering dibl, gate induced drain lowering gidl and body effect m on the subthreshold leakage isub wasinvestigated in detail. The tunnelingbased leakage currents caused where the gate overlaps the drain is referred to as the gateinduced drain leakage gidl. Electrothermally induced parasitic gate leakage etipgl or gl is an environment and materials induced failure mechanism that adversely affects the performance and reliability of an integrated circuit. Pdf analysis of gateinduced drain leakage mechanisms in. For mainmode bits, leakage current can be attributed to junction thermalgeneration leakage current. Dec 10, 2016 praveen meduri ee478 presentation on gate induced drain leakage current. Drain induced barrier lowering dibl is a shortchannel effect in mosfets referring originally to a reduction of threshold voltage of the transistor at higher drain voltages. Pdf investigation of gateinduced drain leakage gidl current. Gateinduced drain leakage gidl current is investigated in singlegate sg ultrathin body field effect transistor fet, symmetrical doublegate dg finfet.
Impact of interface traps on gateinduced drain leakage. Impact of gateinduced drain leakage current on the tail. Gate induced leakage and drain current offset in organic. Gidl sets an upper limit on the vlsi mosfet scaling and may even. Investigation of gateinduced drain leakage gidl current in. This current is found to be due to the bandtoband tunneling occurring in the deepdepletion layer in the gate to drain overlap region. Gate induced drain leakage gate induced drain leakage gidl occurs due to band to band tunneling at gate drain overlap region under the strong electric field. Gate induced drain leakage gidl current is investigated in single gate sg ultrathin body field effect transistor fet, symmetrical double gate dg finfet, and asymmetrical dg metal oxide semiconductor field effect transistor mosfet devices. Gateinduced drainleakage gidl programming method for soft. One of such schemes is shown in figure 5, where the body voltage sweeps with all other terminals grounded and the. Trapassisted tunneling effects on gate induced drain leakage in silicongermanium channel pfet conference paper pdf available september 2015 with 188 reads how we measure reads. Hotelectroninduced device degradation during gateinduced. The leakage in the drain region is a crucial issue for scaling of the mosfet towards the deep submicron regime.
This paper underlines a closed forms of mosfet transistorsleakage current mechanisms inthe sub 100nmparadigm. Generic interface definition language, an extension to corba idl. Index termsdisturbance, finfet, gateinduced drain leak. Hot carrier effect on gateinduced drain leakage current in. Here, the effect of fin shape on the leakage currents like gate induced drain leakage and subthreshold leakage is evaluated. The gidl current depends only upon conditions in the immediate gate to drain. For example, one circuit component that is the building block of digital logic functions, including data storage memory circuits is the socalled field effect transistor. Us6097070a mosfet structure and process for low gate. The resulting drain to body current is called gate induced drain leakage gidl current. Leakage current mechanisms and leakage reduction techniques. Citeseerx document details isaac councill, lee giles, pradeep teregowda.
Impact of gate induced drain leakage on overall leakage of submicrometer cmos vlsi circuits oleg semenov, andrzej pradzynski, member, ieee, and manoj sachdev, senior member, ieee abstract in this paper, the impact of gate induced drain leakage gidl on the overall leakage of submicrometer vlsi circuits is studied. Lower sige bandgap makes gate induced drain leakage gidl important for low leakage, high threshold voltage device designs. Gate induced drain leakage, a leakage mechanism in mosfets due to large field effect in the drain junction. Significant gate induced drain leakage current can be detected in thin gate oxide mosfets at drain voltages much lower than the junction breakdown voltage. Gate oxide thickness and gate polysi etching condition dependence, 1998 3rd international symposium on plasma process induced damage, pp. Accurate leakage current models for mosfet nanoscale. Hot carrier effect on gateinduced drain leakage current.
In this letter, the effect of prehaloldd ge preamorphization. Impact of gateinduceddrainleakage current modeling on. Gidl current is one of the major drain leakage components and is generated in the overlapped region of the gate and the drain. Impact of gate induced drain leakage and impact ionization. Gate induced drainleakage gidl programming method for softprogrammingfree operation in uni. When the drain is connected to a positive bias and. Cristoloveanua a imeplahc, inpgrenoble, minatec, 3 parvis louis neel, bp 257, 38016 grenoble, france. The impact of gateinduced drain leakage current on mosfet. Drain induced barrier lowering dibl qualitative 6 in shortl g mosfet. Sram cell leakage control techniques for ultra low power. This paper explores the various transistor intrinsic leakage mechanisms including the weak inversion, the drain induced barrier lowering, the gate induced drain leakage, and the gate oxide tunneling. There are still other leakage components, like gate induced drain leakage gidl and punchthrough current, however those ones. Gate oxide thickness and gate polysi etching condition dependence, 1998 3rd international symposium on plasma processinduced damage, pp. Effect of fin shape on gidl and subthreshold leakage currents.
Large vds large depletion layer around drain part of channel surface already depleted lowered barrier vt reduced increased leakage current. In a classic planar fieldeffect transistor with a long channel, the bottleneck in channel formation occurs far enough from the drain contact that it is electrostatically shielded from the drain by the combination of the. Simulated stress distributions along channel length direction of both a and bdevice. Hu, modern semiconductor devices for integrated circuits, figure 75 long channel short channel y x. Asymmetric gateinduced drain leakage and body leakage in. The bandtoband tunneling bbt1012 and trapassisted tunneling15 are the wellknown mechanisms. For nanometer devices, leakage current is dominated by subthreshold leakage, gate oxide tunneling leakage and reversebias pnjunction leakage. However, gateinduced drain leakage gidl is a major concern at low power technology nodes because of bandtoband and trapassisted tunneling tat due. Gateinduced drainleakage gidl programming method for. Gl is a trappedcharge phenomenon found in plastic encapsulated bipolari. Gate induced drain leakage gidl improvement for millisecond flash anneal mfla in dram application. In an nmos transistor, when the gate is biased to form accumulat ion layer in the silicon surface under the gate, the silicon surface has almost the same potential as. The use of silicongermanium as a channel material in highk metal gate first pfet technologies of 32nm and beyond has been widely accepted for high performance and low power applications.
However, gateinduced drain leakage components and mechanisms are dominant compared to all the other leakage mechanisms in high threshold voltage devices. Gidl is a phenomenon which occurs when a high voltage is applied to the drain with the gate grounded, as a result a deepdepletion region is formed underneath the gate to drain overlap region shown in figure. Contribution of gate induced drain leakage to overall leakage and. Gidl is induced by bandtoband tunneling effect in strong accumulation mode and generated in the gatetodrain overlap region. The gidl is more in case of singlediffused drain as compared to doublediffused drain. Under the application of strong vertical and longitudinal fields, the drain region in the overlap region may go into deep depletion as the vertical field tends to invert the region and the longitudinal field sweeps the inverted carriers holes for n channel devices. In an nmos transistor, when the gate is biased to form. Gate induced drain leakage an overview sciencedirect topics. Hote, gate induced drain leakage gidl, on and offstate currents. Gate induced drain leakage i5 gate induced drain leakage gidl is due to high field effect in the drain junction of an mos transistor. Improving the gateinduced drain leakage and onstate. It was found that gidl current dominates the junction leakage even at zero gate bias and nominal drain bias of 1. Silicongermanium sige channel pmosfet is considered as a replacement for silicon channel device for 32nm node and beyond, because of its lower threshold voltage and higher channel mobility.
Electrical field increases with the decreasing the depletion layer at the surface. Sources and reduction for transistors, gates, memories and. The polarity of the source drain doping is independent of the polarity of the central or outer gate conductors. Among the problems caused by these effects is the bandtoband tunnelling bbt of hot carriers in the gate to drain overlap region which is the source of the gate induced drain leakage current.
Mosfet structure and process for low gate induced drain leakage gild download pdf. In an nmos transistor, when the gate is biased to form accumulation layer in the silicon surface under the gate, the silicon surface has almost the same potential as the ptype substrate, and the surface acts like a p region more heavily. Significant gateinduced drain leakage current can be detected in thin gate oxide mosfets at drain voltages much lower than the junction breakdown voltage. Contribution of gate induced drain leakage to overall. The effects of shallow trench isolation sti induced mechanical strain on gate induced drain leakage gidl current in hfbased and sion ntype metal oxide semiconductor field effect transistors.
The impact of gateinduced drain leakage current on. Assenmacher, infineon 2003 isub subthreshold leakage from source ig gate leakage direct tunneling igidlgate induced drain leakage gidl ij junction reversebias leakage relative contributions of offstate leakage but magnitude of total leakage. Here, we have studied the gidl dependence on temperature as well as drain and substrate bias. Hu, stressinduced leakage current due to charging damage. The drain current offset distorts the drain current in the linear region of the transistor performance curve, making it. The polarity of the sourcedrain doping is independent of the polarity of the central or outer gate conductors. Pdf gateinduced drain leakage gidl improvement for. Contribution of gate induced drain leakage to overall leakage. Gate bias induced leakage current and drain current offset limit device performance in poly 3hexylthiophene p3ht organic thin film transistors otfts. Draininduced barrier lowering dibl is a shortchannel effect in mosfets referring originally to a reduction of threshold voltage of the transistor at higher drain voltages. The fin shape can be changed by varying the top width of the fin. One of the leakage mechanisms which contribute significantly to power dissipation is the gate induced drain leakage gidl.
Citeseerx suppression of gate induced drain leakage. Those three major leakage current mechanisms are illustrated in fig. The tunnelingbased leakage currents caused where the gate overlaps the drain is referred to as the gate induced drain leakage gidl. In a classic planar fieldeffect transistor with a long channel, the bottleneck in channel formation occurs far enough from the drain contact that it is. Analysis of gate induced drain leakage mechanisms in silicongermanium channel pfet article pdf available in ieee transactions on electron devices 615. Leakage current reduction is of primary importance as the technology scaling trends continue towards deep submicrometer regime. Gateinduced drain leakage gidl is another significant leakage mechanism, resulting due to the depletion at the drain surface below the gatedrain overlap region. A large component of offstate leakage current is gate induced drain leakage gidl current, caused by bandto band tunneling in the drain region underneath the gate when there is a large gate to drain bias, there can be sufficient energyband. Implementation and characterization of gate induced drain leakage currentbased multiplexed sinw biosensor jieun lee 1, jung han lee2, mihee uhm1, won hee lee, seonwook hwang1, bong sik choi1, byunggook park2, dong myong kim1, and dae hwan kim1, 1school of electrical engineering, kookmin university, seongbuk gu, seoul, 6 702, korea 2school of electrical engineering and computer. It is found that the gidl method effectively suppresses soft programming without sacri.
Major contributors to the gate leakage current are the gate oxide tunneling and the injection of hot carrier from substrate to gate oxide. Electric field, ez, gate induced drain leakage current, igidl, and surface potential have been modeled. Us7359271b2 gate induced drain leakage current reduction by. The underlying assumptions of the previously proposed extraction methods are exposed and their ability to capture bandtotrap mechanisms is discussed. Analysis of gate induced drain leakage characteristics and threshold voltage modulation of plasmadoped finfets for lowpower applications jimyoung lee et al gate induced drain leakage reduction with analysis of gate fringing field effect on highmetal gate cmos technology esan jang et albody doping profile of select device to.
Since the channel must be depleted of charge before inversion takes place, any help on depletion process will reduce vt. Praveen meduri ee478 presentation on gate induced drain leakage current. Accurate leakage current models for mosfet nanoscale devices. Cristoloveanua a imeplahc, inpgrenoble, minatec, 3 parvis louis neel, bp 257, 38016 grenoble, france bcealeti, minatec, 17 avenue des martyrs, 38054 grenoble cedex 9, france cschool of engineering, brown university, providence, ri 02912, usa. The impact of the gate induced drain leakage and impact ionization currents on hysteresis of pd fb soi circuits is examined, and a physical understanding is provided. This diagram, based on a comprehensive paper by roy et al. This paper investigates the effect of the asymmetric source and drain geometries of surroundgate vertical mosfets on the drain leakage currents in the offstate region of operation. For tailmode bits, it is found for the first time that gate induced drain leakage gidl current has a dominant impact. The charges trapping in the gate oxide and the defects at the sisio 2 interface have also undesirable effects on the degradation and ageing of mosfet. Hu, stress induced leakage current due to charging damage. A study on hci induced gate leakage current model used for reliability simulations in 90nm nmosfets nobukazu tsukiji h.
Gidl current is a result of depletion at drain surface below the gate drain overlap region. A study on hci induced gate leakage current model used for. Gate induced drain leakage an overview sciencedirect. Measured silicon data from 90nm and 65nm pd soi technologies indicate that both components dominate in the substrate currents at zero gate voltage and nonzero drain voltages. In this letter, the effect of prehaloldd ge preamorphization implant pai on gidl and performance is investigated using experimental data and simulations. Investigation of gateinduced drain leakage gidl current.
Finfets have emerged as the solution to short channel effects at the 22nm technology node and beyond. Measured reductions in gidl current for sg and dg thinbody devices are reported for the first time. Implementation and characterization of gateinduced drain. In this paper, an analytical paradigm for the gate induced drain leakage gidl for shallow extension engineered dual metal surrounding gate seedmsg mosfet using superposition technique with appropriate boundary conditions is proposed. Gateinduced drain leakage gidl is caused by high field effect in the drain junction of. This is a measure of gate leakage of a logic gate during its steady state. Measurements of gateinduced drain leakage gidl and.
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