TEMPERATURE-COEFFICIENT OF RESOLUTION OF LATERAL BIPOLAR MAGNETOTRANSISTORS

We present measurement results of the temperature coefficient (TC) of magnetic field resolution B(min) for dual-collector lateral bipolar ma gnetotransistors over a temperature range 273 K less-than-or-equal-to T less-than-or-equal-to 373 K. For a bandwidth of 500 Hz centered arou nd 750 Hz, the resolution turns out to be 600 nT at room temperature w ith a TC of +2.3 x 10(-3)/K. With the magnetotransistor (MT) operating in medium injection, there is very little dependence of B(min) on bia s conditions. In this regime, the correlation (GAMMA) between collecto r noise currents is the highest (near unity), where the forward curren t gain beta of the MT is at its maximum. At higher injection levels, a degradation in GAMMA is observed, possibly due to emitter crowding ef fects, behaving in a manner similar to beta. The degree of coherence a ppears to be dependent on frequency; GAMMA is higher at low frequencie s where the base 1/f noise predominates and GAMMA degrades at higher f requencies when white noise levels from the collector epi region becom e significant.