Other TwoTerminal Devices Intro Schottky Barrier Diodes

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Other Two-Terminal DevicesIntroSchottky
Barrier Diodes
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Two-Terminal Devices Having A Single p-n Junction

• Schottky
• Tunnel
• Varactor
• Photodiode
• Solar Cell

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Other Two-Terminal DevicesOf A Different
Construction

• Photoconductive Cell
• LCD (Liquid-Crystal Display)
• Thermistor

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Schottky-Barrier Diode

• Surface-Barrier/Hot-Carrier Diode

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Schottky-Barrier Diode

• Areas of Application
• Very high frequency range
• Lower noise figure
• Low-voltage or high-current power supplies
• AC-to-DC converters
• Radar systems
• Schottky TTL logic

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Fig. 20.1 Passivated hot-carrier diode
Gold leaf metal contact
Anode ()
Metal
Silicon dioxide screen
Metal semiconductor junction
Metal contact
Cathode (-)
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Fig. 20.2 Comparison of characteristics of
hot-carrier and p-n junction diodes
ID
Hot carrier diode
p-n junction diode
VD
p-n junction diode
Hot carrier diode
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Fig. 20.3 Schottky (hot-carrier) diode (a)
equivalent circuit (b) symbol
(a)
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Fig. 20.4 Approximate equivalent circuit for the
Schottky diode
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Fig. 20.5 Motorola Schottky barrier
devices.(Courtesy Motorola Semiconductor
Products, Incorporated
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Fig 20.6 Characteristics curves for
Hewlett-Packard 5082-2300 series of
general-purpose Schottky barrier diodes.
100
10
Forward current (mA)
IF Temperature Coeffiecient 10?A
-2.3mV/ºC 100?A -1.8mV/ºC 1.0mA
-1.3mV/ºC 10mA -0.7mV/ºC 100mA
-0.2mV/ºC
1
.1
T 100ºC
T 25ºC
T -50ºC
0.1
0
100
200
300
400
700
600
500
Forward voltage (mV)
I-V Curve Showing Typical Temperature Variation
for 5082-2300 Series Schottky Diodes
(a)
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100
500
Reverse current (nA)
2900 2303
100
50
2301 2302 2305
10
0
5
15
10
Reverse voltage (V)
5082-2300 Series Typical Reverse Current vs.
Reverse Voltage at TA 25ºC
(b)
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1.2
1.0
0.8
Capacitance (pF)
0.6
2900 2303
0.3
2301 2302 2305
0.2
0
8
16
12
4
20
VR-Reverse voltage (V)
5082-2300 Series Typical Capacitance vs. Reverse
Voltage at TA 25ºC
(c)
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Reported by

• Roxellen L. Arzaga