SU1465750A1 - Method of measuring concentration and mobility of current carriers in semiconductors - Google Patents

Abstract

This invention relates to a measurement technique. The purpose of the invention is to ensure unambiguity of measurements at a constant magnetic field. The essence of this method of measurement is explained by the operation of the device, in which the semiconductor is superimposed on the outlet of the radio-wave converter 6. Then it is irradiated with an electromagnetic wave H, from the microwave of g-I and is acted upon by a magnetic field from the magnetic system P. 3 achieve a maximum conversion of the electromagnetic wave power Nd measured by the meter 10, of a rectangular waveguide which is excited by a semiconductor in it and propagates from the semiconductor to the microwave g. 1. Then fix The readings and P of the 5 and 10 MOPtHocTH meters are given, and since the wave impedances for the electromagnetic waves of the types and Ho4 in the square waveguide are equal, the concentration and mobility of the current carriers in the semiconductor are calculated from the fluids. 1 il. (/

Description

The invention relates to measurable. This method is intended for determining the concentration and mobility of current carriers in semiconductors by the nondestructive radio wave method of free space.

The purpose of the invention is to ensure the uniqueness of measurement in a constant magnetic field.

The drawing shows a structural diagram of a device for implementing the method for determining the concentration and mobility of current carriers in semiconductors.

A device for implementing the method for determining the concentration and mobility of current carriers in semiconductors contains. Microwave generator 1, valve 2, phase shifter 3, electromagnetic wave filter 4 type H ₄₀ , first power meter 5, transition 6 from a rectangular waveguide to a square waveguide, radio wave converter 7, the probe 8 serving as an electromagnetic wave filter of the type H _Y1 rectangular waveguide, a coaxial-waveguide junction 9, the second power meter 10 and a magnet system 11.

A method for determining51 the concentration and mobility of current carriers in semiconductors is as follows.

Cross microwave electric field _{= E m ^ cos (co t} -Kp) electromagnetic wave type H, turned _on in a semiconductor tsrovodimostyu G 'tok_provodimosti with density = 66 ^ ,.

The charge carriers in a transverse magnetic field with induction B _z are affected by the Lorentz force, which results in the appearance of a Hall field, with a tension vector in the direction of the X axis (X, Y, Z), a rectangular coordinate system.

= ^Β ζ I ^th E _m ^ cos (u> t + (f), (1)

This electromagnetic field excites, in the waveguide, a wave of type H ₀₁ propagating from the semiconductor both towards the microwave generator, so. and vice versa. The power carried by an electromagnetic wave of type H _{0) of the} waveguide, expressed in terms of the power of an electromagnetic wave of type H ₄₀ exciting the Hall field, is determined by the following relation

P _n = l? B * P _and , - ^ ⁿ about. I z «u Z _Ho , (2) where Z _H , Ζ _{Ηο (} is the wave impedance for electromagnetic waves of the type H _<o ^and ^ 01, respectively.

Mobility and concentration [C, n from this ratio are defined as

Ph_oj Z // 0.1. 'n _1o Ζη, ₀ ——— ------— t where is the resistivity of the semiconductor;

e is the electron charge;

d - Hall factor equal to 1 _? 93 in weak fields at and 1 - in strong fields at JU * В _г »1).

If the power P _{n of an} electromagnetic wave of type H _{0 |} measure in the transmitted radiation, then the expression for the concentration and mobility of current carriers in the semiconductor is calculated by the formulas mul_1__ in ~~ t

¹¹ .1 Phqi Zhoi ^r n about ^Z h o

B _s _r - T

(5) (6)

T is the coefficient of transmission of electromagnetic waves through an electric field through a semiconductor.

Expressions (3) and (6) make it possible to uniquely determine the mobility and concentration of current carriers in semiconductors. It is not necessary to change the magnetic field.

The device operates as follows.

The semiconductor is superimposed on the outlet of the radio wave converter 6. It is irradiated with a magnetic wave from the microwave generator 1 and exposed to a magnetic field from the magnetic system 11. Using the phase shifter 3, they achieve the maximum

1465750 conversion of the readings of the second power meter 1.0, which measures the power of the electromagnetic wave Н _{О (a} rectangular waveguide, which is excited in it by a semiconductor and propagates from a semiconductor to a microwave generator 1. Fix the readings of a power meter 5 - Рc _{0 (} and a power meter 10 Р _{N (o} . Due to the fact that the wave resistances for electromagnetic waves of types H _<0 and H ₀₁ in a square waveguide are equal, the Formulas for calculating the concentration and mobility of carriers have the form of current in a semiconductor

Claims (1)

/ A method for determining the concentration and mobility of current carriers in semiconductors, including irradiating a semiconductor with an electromagnetic wave while simultaneously exposing it to a magnetic field, the direction of which coincides with the direction of propagation of the electromagnetic wave, and measuring the parameters of the interacting wave with the semiconductor, characterized in that, with In order to ensure unambiguous * measurement in a constant magnetic field, the semiconductor is irradiated with an electromagnetic wave of type H ₄₀ with a power of P _H1o? measure the power Ρ _{Ηοι of the} electromagnetic wave H _ot interacting with the semiconductor, and the concentration η and the mobility of the current carriers in the semiconductor are determined by the formulas I ^th c ~ t y p _f P N <I_ _Z J4 o <_. Hto ^ Η, ο ....... _Ρ "ΙΟ__Zf £ jo ^Р Н ₀ , ^Ζ Ηθ4 where - wave resistance of electromagnetic waves of types N ₄₀ and N _about ; - resistivity of the semiconductor; is the electron charge; < - magnetic field induction; - Hall factor; - coefficient of transmission of an electromagnetic wave through a semiconductor in the case of a transmitted interacting electromagnetic wave, 1 - in the case of reflected pro ^Ζ Η 40 O1 e ^Β ζ or an interacting electromagnetic wave.