C. Riccobene et al., OPERATING PRINCIPLE OF DUAL COLLECTOR MAGNETOTRANSISTORS STUDIED BY 2-DIMENSIONAL SIMULATION, I.E.E.E. transactions on electron devices, 41(7), 1994, pp. 1136-1148
Dual collector magnetotransistors are magnetic-field-sensitive devices
currently developed in several laboratories. Optimized sensor design
is often attempted by trial and error rather than by established desig
n rules. This motivated the present comprehensive study of the operati
on of magnetotransistors by accurate two-dimensional numerical simulat
ions. We model vertical and lateral transistors as obtained by industr
ial IC technology on the basis of data provided by the chip manufactur
er. We consider the entire device structure with the full, complex dev
ice geometry, and the physically proper boundary conditions. Our simul
ations reveal the details, controversial hitherto, of the operating pr
inciple of these devices. In particular we find that, in the case of t
he vertical transistor, it is essentially the emitter injection modula
tion effect which dominates the sensor response. In the case of the la
teral transistor, the magnetic sensitivity is predominantly determined
by minority-carrier deflection, though side effects are involved as w
ell. Bv variation of the doping profile and the device geometry we der
ive rules for optimized magnetotransistor design.