Spin-valve transistors (SVTs) employing hot-electron transport through ferromagnetic multilayers have large magnetocurrent (MC), making them a promising magnetic field sensor. However, the assembly technique required for fabricating the necessary semiconductor-metal-semiconductor structure limits their use. We have circumvented this problem with an alternative fabrication technique and show a greater than 300% MC change in SVT devices employing a sputter-deposited zinc oxide (ZnO) semiconductor emitter as hot-electron injector. The compatibility of this process to standard fabrication techniques makes it possible to integrate the SVT into present-day industrial technology.Index Terms-RF sputtering, spin-valve transistor (SVT), zinc oxide (ZnO).