Magnetocurrent in a bipolar spin transistor at room temperature

Abstract

A spin transistor which consists of a metallic giant magnetoresistance emitter, a copper base, and a p-n junction was prepared on a Si(100) wafer. The emitter current changes from 1mA at a magnetically parallel state to 0.968mA at a magnetically antiparallel state. At the same states the base currents were 29.3μA and 333nA, respectively, which gave a magnetocurrent ratio of ∼8600% and a transfer ratio of 3×10−2 at room temperature for a common collector configuration. The sensitivity of this spin device is higher than 4000%∕Oe. The memory effect and the high performance make it possible for practical usage. The working principle of this kind of three-terminal spin device can be simply described by circuit theory.

Giant magnetocurrent in silicon-base magnetic tunneling transistor

“…4. Indeed, this operation mechanism is quite similar to a GMR structure with a heavy doped interface p-n junction which will be reported elsewhere [14].…”

Magneto-current study in a silicon base spin valve transistor

“…The detailed fabrication process of the CIP pseudo spin valve transistor can be found in Ref. [3], and Fig. 1 …”

Spin-valve transistor with a NP junction

“…However, the spin injection current is restricted by the break down voltage of the tunneling material. We have recently reported a new type of the ST which combines a MR element with a pnjunction collector [4][5]. Because the resistance difference of the CIP GMR and TMR are large enough to measure, we use an emitter bias and a base resistor in the MC measurement.…”

“…To leave a barrier between the emitter and base, and change the measurement circuitry, the fabrication of this ST becomes simpler and the performances of the spin transistors are increased. For simplifications of the experiments, the most previous experiments were used the metal shadow masks and the width of the transistors is over hundreds microns [3][4][5][6][7][8]. In this study, we define the microstructure of the SVT by a standard lift-off process using E-beam lithography to fabricate 0.5 um-wide SVT.…”