Physics of Semiconductors: Applications of MIS Diodes in Flash Memory

Physics of semiconductors
Student name1
Department, university
Address, containing the country name
1.0 Abstract-Diodes are used in various
applications due to their excellent features
and characteristics. Various types of diodes
are available for various applications. MIS
diodes for instance have been used in Flash
memory technology for efficient operations.
Despite of numerous problems facing the
current flash memory devices, the use of
nano-structures as storage elements have
been identified as potential for eliminating
the current problems and improving on the
efficiency of devices.
Keywords
Mis diode, flush memory, silicon
nanostructures
2.0 Introduction
Diodes are very significant in life as they
constitute the major components of logic
gates, transistor, amplifiers and integrated
circuits [2-4]. Depending on the desired
applications, there are several types of
diodes available. Metal insulator
semiconductor diode (MIS) is highly used in
the research and study of semiconductor
surfaces owing to their stability and
reliability. Presently, MIS diodes are used in
various electronics operations [7].
MISs can be further classified into different
categories like the metal oxide silicon.
Basically, MIS structure is viewed as a
voltage-capacitance related [4]. When
appropriate voltage is applied to the charge
coupled device, electrical charges are moved
across the entire semiconductor substrate in
a very controlled manner [8]. Therefore,
charge coupled devices have been used in a
variety of applications such as the logic
operations and signal processing. Figure 1
shows a schematic of a metal insulator
semiconductor diode.
Figure 1: Metal insulator semiconductor
diode
In this report, applications of an MIS diode
in the electrical charging mechanism of
Flash memory is investigated. It is based on
the description of the diode current-voltage
and current-capacitance relations.
Furthermore, the general working principle
of flash technology and associated problem
are presented.
3.0 Experimental Section
Requirements
 MIS diodes
 Flash memory device
 Connecting wires
 Power supply
 Digital multimeter
Procedure
1. The metal-insulator-semiconductor
(MIS) diodes were fabricated on
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silicon layer substrates. First, by a
diluted hydrogen fluoride (DHF) was
used to clean the silicon substrates.
Ultra-pure water (UPW) was then
used for rinsing operations for some
time to avoid surface roughness.
Finally, argon was used to pre-
sputter the hafnium target just before
film deposition.
2. Through the appropriate connection,
the electrical charging mechanism in
flash memory was examined and
analyzed.
3. Currents, voltages, capacitance and
time data were measure and recorded
in Microsoft Excel. Graphs for
current-voltage and capacitance
voltage were plotted and analyzed.
4. Discussions questions were finally
represented.
4.0 Results and discussion
From the recorded data, the following
graphs were plotted.
-40 -30 -20 -10 0 10 20 30 40
-0.000000001
-8E-10
-6E-10
-4E-10
-2E-10
0
2E-10
4E-10
6E-10
8E-10
0.000000001
Curent vs Voltage
Voltage (V)
Current (A)
Figure 2: Graph representing the Current vs
Voltage of the MIS diode
-40 -30 -20 -10 0 10 20
-2.00E-10
-1.00E-10
0.00E+00
1.00E-10
2.00E-10
3.00E-10
4.00E-10
Current vs Voltage
Voltage (V)
Current (A)
Figure 3: Graph representing the Current vs
Voltage of the MIS diode
-40 -30 -20 -10 0 10 20
1.39E-10
1.40E-10
1.41E-10
1.42E-10
1.43E-10
1.44E-10
1.45E-10
1.46E-10
Capacitance vs Voltage
Voltage (V)
Capacitance (F)
Figure 4: Graph representing the
Capacitance vs Voltage of the MIS diode
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