《半导体物理器件基础》课后matlab

Matlab exercises

Exercise5.7

%initialization

clc;

clear;

%evaluation

q=1.6e-19;

e0=8.85e-14;

ni=1.0e10;

K=1.38e-23;

T=300;

KS=11.8;

%input variables

NA=input('Input the p-side doping,NA= ');

ND=input('Input the n-side doping,ND= ');

j=input('Input the number of times you want to circulate: '); VA=input('Input the applied Voltage,VA= ');

%main program

for j1=1:j

Vbi=K*T*log(NA*ND/ni^2);

X=(2*KS*e0)/q*(Vbi-VA);

xn=sqrt(X*NA/(ND*(NA+ND)));

xp=sqrt(X*ND/(NA*(NA+ND)));

%p-side

x=linspace(-xp,0);

Vp=(q*NA/(2*KS*e0))*(x+xp).^2;

Ep=-(q*NA/(KS*e0))*(x+xp);

%n-side

xx=linspace(0,xn);

Vn=Vbi-VA-(q*ND/(2*KS*e0))*(xn-xx).^2;

En=-(q*ND/(KS*e0))*(xn-xx);

xxx=[xx,2*xn];

Vn=[Vn,Vn(100)];

if j1==1

E0=-(q*NA/(KS*e0)*xp);

V0=Vbi-VA;

Emin=1.1*E0;

Vmax=1.1*V0;

xmax=2.5*max(xn,xp);

fprintf('\nRESULT\n')

NA,ND,VA,Vbi,xn,xp,W=xn+xp,E0,V0

else

end

subplot(2,1,1),plot(x,Vp,xxx,Vn);

axis([-xmax,xmax,0,Vmax]);grid on

xlabel('x(cm)');ylabel('V(volts)');

hold on

subplot(2,1,2),plot(x,Ep,xx,En);

axis([-xmax,xmax,Emin,0]);grid on

xlabel('x(cm)'),ylabel('E(volts/cm)'); hold on

VA=VA/2;

end

Exercise6.9

%Initialization

clc

%evaluation

T=300;

q=1.6e-19;

k=2.38e-23;

%main program

VA=linspace(-0.5,0.1);

I1=exp(q*VA./(k*T))-1;

I2=I1-1;I3=I2-1;I4=I3-1;

I=[I1;I2;I3;I4];

%plot figure

plot(VA,I)

axis([-0.5 0.1 -6 6]);grid

xlabel('VA(volts)');ylabel('I/I0'); text(-0.31,-0.7,'IL/I0=0');

text(-0.31,-1.7,'IL/I0=-1');

text(-0.31,-2.7,'IL/I0=-2');

text(-0.31,-4.7,'IL/I0=-4');

hold on

Exercise7.6

%Initialization

clc

%evaluation

A=6e-3;

q=1.6e-19;

Kse0=11.8*8.85e-14;

%Input

C=rand(1,23);

VA=rand(1,23);

CJ=rand(1,23);

NB=rand(1,23);

x=rand(1,23);

for j=1:23

C(j)=input('input the capacity C= ');

VA(j)=input('input the reverse voltage VA= ');

CJ(j)=C(j)-2;

end

%main program

for j=1:23

if j>=2

NB(j)=2/((q*Kse0*A^2)*abs((CJ(j)-CJ(j-1))/(VA(j)-VA(j-1)))); x(j)=Kse0*A/CJ(j);

else

end

end

%plot

plot(x([2,23]),NB([2,23]))

axis([2e-16 7e-16 1e34 1.2e36]);grid

xlabel('x(cm)'),ylabel('NB(/cm3)');

hold on