Drain-induced barrier lowering

About: Drain-induced barrier lowering is a research topic. Over the lifetime, 6163 publications have been published within this topic receiving 101547 citations.

Revisited parameter extraction methodology for electrical characterization of junctionless transistors

Abstract: Several electrical parameters characterize device performance, electron transport and doping level in MOS transistors. In this paper, Junctionless Transistors (JLTs) fabricated on (100) silicon on insulator (SOI) wafer with 145 nm thick BOX and 9 nm silicon thickness were considered. Parameter extraction methodologies were revisited in order to account for the unique electrical properties of JLT devices. The deduced parameters, such as threshold voltage, flat-band voltage, drain induced barrier lowering (DIBL), low field mobility and channel doping level, are shown to reveal the specific features of JLT compared to conventional inversion-mode transistors.

Punch-through field effect transistor

Abstract: A trenched field effect transistor suitable especially for low voltage power applications provides low leakage blocking capability due to a gate controlled barrier region between the source region (44) and drain region (40). Forward conduction occurs through an inversion region between the source region (44) and drain region (40). Blocking is achieved by a gate controlled depletion barrier. Located between the source (44) and drain (40) regions is a fairly lightly doped body region (42). The gate electrode (52A), located in a trench (50A), extends through the source (44) and body (42) regions and in some cases into the upper portion of the drain region (40). The dopant type of the polysilicon gate electrode (52A) is the same type as that of the body region (42). The body region (42) is a relatively thin and lightly doped epitaxial layer grown upon a higly doped low resistivity substrate of opposite conductivity type. In the blocking state the epitaxial body region is depleted due to applied drain-source voltage, hence a punch-through type condition occurs vertically. Lateral gate control increases the effective barrier to the majority carrier flow and reduces leakage current to acceptably low levels.

Method for forming asymmetric dual gate transistor

Abstract: The present invention provides a double gated transistor and a method for forming the same that results in improved device performance and density. The preferred embodiment of the present invention provides a double gated transistor with asymmetric gate doping, where one of the double gates is doped degenerately n-type and the other degenerately p-type. By doping one of the gates n-type, and the other p-type, the threshold voltage of the resulting device is improved. Additionally, the preferred transistor design uses an asymmetric structure that results in reduced gate-to-drain and gate-to-source capacitance. In particular, dimensions of the weak gate, the gate that has a workfunction less attractive to the channel carriers, are reduced such that the weak gate does not overlap the source/drain regions of the transistor. In contrast the strong gate, the gate having a workfunction that causes the inversion layer to form adjacent to it, is formed to slightly overlap the source/drain regions. This asymmetric structure allows for the performance benefits of a double gate design without the increased capacitance that would normally result.

Analysis of Short-Channel Schottky Source/Drain Metal-Oxide-Semiconductor Field-Effect Transistor on Silicon-on-Insulator Substrate and Demonstration of Sub-50-nm n-type Devices with Metal Gate

Abstract: The Schottky source/drain metal-oxide-semiconductor field-effect transistor (MOSFET) has potential for scaling to the nanometer regime, because low electrode resistances with very shallow extension can be realized using metal source/drain. In this study, very short channel n- and p-type Schottky source/drain MOSFETs with silicon-on-insulator (SOI) structure were analyzed theoretically, and n-type devices were demonstrated experimentally. It was shown theoretically that a drivability of the Schottky source/drain MOSFET comparable to that of conventional MOSFETs can be realized with a low Schottky barrier height. The short-channel effect can be suppressed even with a 15-nm-long channel at tOX = 1 nm and tSOI = 3 nm. The room-temperature operation of sub-50-nm n-type ErSi2 Schottky source/drain MOSFETs on a separation by implanted oxygen (SIMOX) substrate was demonstrated.

An As-P(n + -n - )double diffused drain MOSFET for VLSI's

Abstract: An As-P(n+-n-) double diffused drain is characterized as one of the most feasible device structures for VLSI's from the overall viewpoint of device design. This device makes good use of both As, suitable for microfabrication, and P, in realizing a graded junction. The feasibility of this double diffused drain is investigated comparing it with a conventional As drain over the wide range of effective channel length from 0.5 to 5 µm. We have also succeeded in directly measuring hot-hole gate current as low as on the order of 10-15A. This current seems to have an important influence on the hot-carrier effects. On the basis of the experiments and simulations using the two-dimensional process/device analysis programs SUPREM and CADDET, it is shown that this device structure provides remarkable improvements, not only in terms of channel hot-electron effects, but also avalanche hot-carrier effects, which are more responsible for hot-carrier related device degradation due to impact ionization at the drain. In addition, this structure has almost the same short channel effect characteristics, for example threshold-voltage lowering as a conventional MOSFET.