From b1f5c3f8d6671b4331cef1dcebdf63b7a43a3a2b Mon Sep 17 00:00:00 2001
From: priyanka
Date: Wed, 24 Jun 2015 15:03:17 +0530
Subject: initial commit / add all books

---
 284/CH4/EX4.1/ex_1.sce | 15 +++++++++++++++
 284/CH4/EX4.2/ex_2.sce | 10 ++++++++++
 284/CH4/EX4.3/ex_3.sce | 22 ++++++++++++++++++++++
 284/CH4/EX4.4/ex_4.sce | 11 +++++++++++
 284/CH4/EX4.5/ex_5.sce | 10 ++++++++++
 284/CH4/EX4.6/ex_6.sce |  9 +++++++++
 284/CH4/EX4.7/ex_7.sce | 17 +++++++++++++++++
 7 files changed, 94 insertions(+)
 create mode 100755 284/CH4/EX4.1/ex_1.sce
 create mode 100755 284/CH4/EX4.2/ex_2.sce
 create mode 100755 284/CH4/EX4.3/ex_3.sce
 create mode 100755 284/CH4/EX4.4/ex_4.sce
 create mode 100755 284/CH4/EX4.5/ex_5.sce
 create mode 100755 284/CH4/EX4.6/ex_6.sce
 create mode 100755 284/CH4/EX4.7/ex_7.sce

(limited to '284/CH4')

diff --git a/284/CH4/EX4.1/ex_1.sce b/284/CH4/EX4.1/ex_1.sce
new file mode 100755
index 000000000..ff37a0aaf
--- /dev/null
+++ b/284/CH4/EX4.1/ex_1.sce
@@ -0,0 +1,15 @@
+// Chapter 4_Carrier Transport Phenomenon
+//Caption_Carrier drift
+//Ex_1//page 134
+T=300    //temperature in kelvin
+Na=0
+e=1.6*(10^-19)
+Nd=10^16    //donor concentration in per cm cube
+E=10   //Applied electric field in V/cm
+ni=1.8*(10^6)
+n=(Nd-Na)/2+(((Nd-Na)/2)^2+ni^2)^0.5
+p=ni^2/n
+muN=8500   //mobility of electron in  gallium arsenide in cm^2/V-s
+mup=400
+J=e*(muN*n+mup*p)*E
+printf('The drift current density for this electric field is %1.2fd A/cm^2',J )
\ No newline at end of file
diff --git a/284/CH4/EX4.2/ex_2.sce b/284/CH4/EX4.2/ex_2.sce
new file mode 100755
index 000000000..8d8a0b908
--- /dev/null
+++ b/284/CH4/EX4.2/ex_2.sce
@@ -0,0 +1,10 @@
+// Chapter 4_Carrier Transport Phenomenon
+//Caption_Carrier drift
+//Ex_2//page 143
+T=300
+sig=16   //CONDUCTIVITY IN (OHM-CM)^-1
+Na=10^16   //acceptor doping concentration
+e=1.6*(10^-19)
+// sig=e*muN*(Nd-Na)
+//By trial and error
+printf('Doping concentration is 3.5*10^17 cm^-3 and mobilityis 400 cm^2/V-S')
\ No newline at end of file
diff --git a/284/CH4/EX4.3/ex_3.sce b/284/CH4/EX4.3/ex_3.sce
new file mode 100755
index 000000000..bae394eba
--- /dev/null
+++ b/284/CH4/EX4.3/ex_3.sce
@@ -0,0 +1,22 @@
+// Chapter 4_Carrier Transport Phenomenon
+//Caption_Conductivity
+//Ex_2//page 144
+T=300
+Nd=5*(10^15)    //donor concentration
+R=10   //resistance in kohm
+J=50    //current density in A/cm^2
+V=5   //voltage  in volts
+i=V/R    //current
+A=i/J    //cross sectional area
+E=100
+L=V/E   //length of the resistor
+pho=L/(V*A)
+// The conductivity of a compensated p-type semiconductor is
+//pho=e*muP*(Na-Nd)
+//where the mobilty is a function of the total ionized impurity concentration Na+Nd
+//Using trial and error , if
+ Na=1.25*(10^16)
+ muP=410
+ e=1.6*(10^-19)
+sig=e*muP*(Na-Nd)
+printf('Conductivity obtained is %1.2fd which is very close to the value we need',sig)
\ No newline at end of file
diff --git a/284/CH4/EX4.4/ex_4.sce b/284/CH4/EX4.4/ex_4.sce
new file mode 100755
index 000000000..f040adcf5
--- /dev/null
+++ b/284/CH4/EX4.4/ex_4.sce
@@ -0,0 +1,11 @@
+// Chapter 4_Carrier Transport Phenomenon
+//Caption_Carrier diffusion
+//Ex_4//page 150
+T=300
+d=0.10   //distance in cm over which concentration varies
+Dn=225    //diffusion coefficient
+e=1.6*(10^-19)
+delN=1*(10^18)-7*(10^17)
+J=e*Dn*(delN/d)
+printf('The diffusion current density is %1.2fd A/cm^3',J)
+
diff --git a/284/CH4/EX4.5/ex_5.sce b/284/CH4/EX4.5/ex_5.sce
new file mode 100755
index 000000000..641907e26
--- /dev/null
+++ b/284/CH4/EX4.5/ex_5.sce
@@ -0,0 +1,10 @@
+// Chapter 4_Carrier Transport Phenomenon
+//Caption_Graded impurity distribution
+//Ex_5//page 153
+T=300
+x=0   //given 0<x<1 micrometer
+Nd=10^16-10^19*x
+//Taking the derivative of donor concentration , we have d(ND)/dx=-10^19
+e=1.6*(10^-19)
+Ex=-(0.0259)*(-10^19)/Nd
+printf('The induced electric field is %1.1fd V/cm',Ex)
\ No newline at end of file
diff --git a/284/CH4/EX4.6/ex_6.sce b/284/CH4/EX4.6/ex_6.sce
new file mode 100755
index 000000000..eab9f9d5d
--- /dev/null
+++ b/284/CH4/EX4.6/ex_6.sce
@@ -0,0 +1,9 @@
+// Chapter 4_Carrier Transport Phenomenon
+//Caption_The Einstein relation
+//Ex_6//page 155
+T=300
+mu=1000    //mobility of a particular carrier
+kT=0.0259
+e=1.6*(10^-19)
+D=(kT)*mu
+printf('Diffusion coefficient is %1.2fd cm^2/s ',D)
\ No newline at end of file
diff --git a/284/CH4/EX4.7/ex_7.sce b/284/CH4/EX4.7/ex_7.sce
new file mode 100755
index 000000000..8948c7970
--- /dev/null
+++ b/284/CH4/EX4.7/ex_7.sce
@@ -0,0 +1,17 @@
+// Chapter 4_Carrier Transport Phenomenon
+//Caption_The Hall Effect
+//Ex_7//page 158
+L=10^-3    //LENGTH IN M
+W=10^-2    //WIDTH IN CM
+d=10^-5
+Ix=10^-3   //current in Amp
+Vx=12.5
+e=1.6*(10^-19)
+Bz=500    //magnetic field in gauss
+Vh=-6.25*10^-3    //hall voltage
+
+//A negative hall voltage for this geometry implies that we have an n-type semiconductor
+BzT=Bz*10^-4   //magnetic field in tesla
+n=-(Ix*BzT)/(e*d*Vh*10^6)
+mun=(Ix*L)/(e*n*Vx*W*d)
+printf('Majority carrier concentration is %1.1fd cm^-3 and mobility is %1.1fd cm^2/V-s ',n,mun)
-- 
cgit