SU1684718A2 - Measuring generator - Google Patents

Abstract

The invention relates to electrical measurement techniques and can be used to measure parameters of semiconductor devices having negative portions on current-voltage characteristics (IVC). The purpose of the invention is to expand the functionality and increase the accuracy of measurement of the parameters of semiconductor devices with a negative VAC section. The generator contains inductance 1, holder 2 of a semiconductor device with negative IVC, negatron 3, power source 4, coupling capacitor 5, first calibrated variable resistor 6, buffer cascade 7, amplifier 8, meter 9 low voltage and resistance, frequency meter 10, unit 11 calibrated capacitors, a switch of 12 measurement ranges, a second calibrated variable resistor 13 and a measurement mode switch 14. 1 il.

Description

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The invention relates to the technique of electrical measurements and can be used to measure the parameters of semiconductor devices having negative portions on the current-voltage characteristics (VAC), and is an improvement of the invention according to the author. St. No. 338861.

The purpose of the invention is to expand the functionality and increase the accuracy of measurement of the parameters of semiconductor devices with a negative VAC section.

The drawing shows the block diagram of the measuring generator.

The device contains inductance 1, holder 2 semiconductor with negative VAC (negatron), negatron 3, power source 4, coupling capacitor 5, first calibrated variable resistor 6, buffer cascade 7, amplifier 8, meter 9 low voltage and resistance, frequency meter 10, a block 11 of calibrated capacitors, a switch 12 for measuring ranges, a second calibrated variable resistor 13, and a switch 14 for measuring mode of meter 9.

The first output of inductance 1 is connected via power supply 4 to the common bus, and the second output is connected to the first output of the negatron holder 2, the first output of separation capacitor 5, to the input of the buffer stage 7 and the common point of the capacitors of the block 11 calibrated capacitors, the second output of the separation capacitor is the first input of the switch 14 measurement mode and through the first calibrated resistor b with OBO 00

X XI

00

ND

the second output of the holder 2 is connected to the common bus, the negatron 3 is connected to the outputs of the holder 2 of the negatron, the output of the buffer stage 7 is connected to the input of the amplifier 8, the amplifier 8 has two outputs, the first of which is connected to the second input of the switch 14, and the second connected to the frequency meter 10, the output of the measurement mode switch 14 is connected to the input of the meter 9 low voltages and resistances, the separate terminals of the capacitors of the block 11 of the calibrated capacitors are connected to the corresponding input of the switch 12 measuring ranges Nij, and the output of the switch 12 via a second calibrated resistor 13 is connected to the common bus.

The device works as follows.

Before starting the measurements, the calibrated variable resistors B and 13 are short-circuited, and the measurement range switch 12 is brought to the initial position and the voltage of the power source A is set equal to the negatron voltage 3 at the operating point. Then, the first calibrated variable resistor, for example, a multi-turn rheostat, is adjusted to the occurrence of stable oscillations with a minimum amplitude, and the alternating voltage through the buffer stage 7, for example, a stream follower, is fed to the input of step 0.

If the amplitude of the oscillations determined by the indications of the meter 9 low voltage and resistance does not exceed the set value, the lower frequency fii of the range is read according to the indications of the frequency meter 10 and the result is fixed. After that, the value of the first calibrated variable resistor 6 and the corresponding negative differential resistance (ODS) of the negatron are determined by connecting a low voltage and resistance meter to the first calibrated variable resistor 6 through the measurement mode switch 14 and measuring its resistance. Then, the second calibrated variable resistor 13, for example, a multi-turn rheostat, is adjusted until the oscillations break down and their secondary excitation is at a much higher frequency. After establishing the oscillation process with a minimum amplitude, the upper frequency fn of the oscillation range of the generator is read. Negatron capacitance value given

bias voltage is determined by the formula

c (t) ".

where CN is the value of the negatron capacity;

Ck is the value of the calibrated capacitance depending on the position of the switch 12.

If necessary, measure other

-N R values See the negatron VAC section with negative resistances, adjustable resistors 6, 13 are short-circuited again, set a new bias voltage value on the negatron and the cycle

measurements are repeated.

The device is reliable in operation, economical, provides high performance measured 1st, which indicates a high economic efficiency.

Claims (1)

Invention Formula Measuring generator auth. St. No. 338861, characterized in that, in order to expand the functionality and increase the measurement accuracy, a block of calibrated capacitors, a switch of measurement ranges, a second calibrated variable resistor and a frequency meter are inserted, the first output of the second calibrated The variable resistor is connected to the common bus, and its second output is through a measurement range switch with the first output of one of the capacitors in the calibrated capacitor bank, the second terminals of which are connected to the potential output of the measured negatron, and the frequency counter input is connected to the amplifier output.