Lake Shore Cryotronics Measure Ready M91 FastHall, Руководство пользователя

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18 CHAPTER 1: Introduction
MeasureReady™ M91 FastHall™ Measurement Controller
Here, is the amount µ
H
must increase to obtain a true value. If l/w = 3, and
c/w = 0.2, then , which is certainly a significant error.
Reduce the contact-size error to acceptable levels by placing contacts at the ends of
contact arms (FIGURE 1-14)
1 . The following aspect ratios yield small deviations from
the ideal:
p c c w 3 l 4 w
     
.
FIGURE 1-14
Contacts at the end of the contact arms
1.5.7.2 Ideal Measurements of Samples with Hall Bar Structure
A typical Hall bar is shown in FIGURE 1-10. In a Hall bar, the current source is always
connected to contacts 5 and 6. The voltage can be measured between any of the four
contacts on the sides of the Hall bar.
1.5.7.2.1 Hall Voltage Measurements on Hall Bar Samples
In the ideal Hall bar structure, the Hall voltage is the voltage between contacts 3 and
4 or contacts 2 and 1.
1. David, J.M. and Buehler, M.G., “A numerical analysis of various cross sheet resistor test structures”,
Solid-State Electron. 20 (Aug 1977) 539-543.