| abstract |
A spin transistor (10) comprises a spin injector (50) formed of a ferromagnetic material and constituting the emitter (20) of a three-terminal device, a spin filter (70) also formed of a ferromagnetic material and constituting a collector (40), and a semiconductor base (30) region. A tunnelling barrier (60) is formed of an insulating metal oxide such as aluminium oxide between the emitter (20) and the base (30). The tunnelling barrier (60) reduces the degree of spin depolarization as carriers are injected into the base (30), and permits selection of spin injection energy. In preferred embodiments, a second tunnelling barrier (80) may be formed between the base (30) and the collector (40). A method of manufacture is also provided. |