A spin metal-oxide-semiconductor field-effect transistor using half-metallic-ferromagnet contacts for the source and drain

A numerical simulation of spin-dependent quantum transport for a spin field effect transistor (spinFET) is implemented in a widely used simulator nanoMOS. This method includes the effect of both spin relaxation in the channel and the tunneling barrier between the source/drain and the channel. Account for these factors permits setting more realistic performance limits for the transistor, especially the magnetoresistance, which is found to be lower compared to earlier predictio...

We review several proposed spintronic devices that can provide new functionality or improve available functions of electronic devices. In particular, we discuss a high mobility field effect spin transistor, an all-metal spin transistor, and our recent proposal of an all-semiconductor spin transistor and a spin battery. We also address some key issues in spin-polarized transport, which are relevant to the feasibility and operation of hybrid semiconductor devices. Finally, we d...

A magnetic-field-effect transistor is proposed that generates a spin-polarized current and exhibits a giant negative magnetoresitance. The device consists of a nonmagnetic conducting channel (wire or strip) wrapped, or sandwiched, by a grounded magnetic shell. The process underlying the operation of the device is the withdrawal of one of the spin components from the channel, and its dissipation through the grounded boundaries of the magnetic shell, resulting in a spin-polariz...

In a recent e-print [cond-mat/0603260] Hall and Flatte claim that a particular spin based field effect transistor (SPINFET), which they have analyzed, will have a lower threshold voltage, lower switching energy and lower leakage current than a comparable metal oxide semiconductor field effect transistor (MOSFET). Here, we show that all three claims of HF are invalid.

A vertical spin metal-oxide-semiconductor field-effect transistor (spin MOSFET) is a promising low-power device for the post scaling era. Here, using a ferromagnetic-semiconductor GaMnAs-based vertical spin MOSFET with a GaAs channel layer, we demonstrate a large drain-source current IDS modulation by a gate-source voltage VGS with a modulation ratio up to 130%, which is the largest value that has ever been reported for vertical spin field-effect transistors thus far. We find...

We fabricated and characterized a new spin-functional MOSFET referred to as a pseudo-spin-MOSFET (PS-MOSFET). The PS-MOSFET is a circuit using an ordinary MOSFET and magnetic tunnel junction (MTJ) for reproducing functions of spin-transistors. Device integration techniques for a bottom gate MOSFET using a silicon-on-insulator (SOI) substrate and for an MTJ with a full-Heusler alloy electrode and MgO tunnel barrier were developed. The fabricated PS-MOSFET exhibited high and lo...

Current interest in spintronics is largely motivated by a belief that spin based devices (e.g. spin field effect transistors) will be faster and consume less power than their electronic counterparts. Here we show that this is generally untrue. Unless materials with extremely strong spin orbit interaction can be developed, the spintronic devices will not measure up to their electronic cousins. We also show that some recently proposed modifications of the original spin field ef...

A common issue in low temperature measurements of enhancement-mode metal-oxide-semiconductor (MOS) field-effect transistors (FETs) in the low electron density regime is the high contact resistance dominating the device impedance. In that case a voltage bias applied across the source and drain contact of a Hall bar MOSFET will mostly fall across the contacts (and not across the channel) and therefore magneto-transport measurements become challenging. However, from a physical p...

We theoretically investigate spin dependent transport in ferromagnetic/normal metal/ferromagnetic single electron transistors by applying master equation calculations using a two dimensional space of states involving spin and charge degrees of freedom. When the magnetizations of ferromagnetic leads are in anti-parallel alignment, the spins accumulate in the island and a difference of chemical potentials of the two spins is built up. This shift in chemical potential acts as ch...

Spin-based memories are attractive for their non-volatility and high durability but provide modest resistance changes, whereas semiconductor logic transistors are capable of large resistance changes, but lack memory function with high durability. The recent availability of multiferroic materials provides an opportunity to directly couple the change in spin states of a magnetic memory to a charge change in a semiconductor transistor. In this work, we propose and analyze the sp...