A TRAPATT diode has the doping concentration NA = 2 x 1015/cm3 and a current density of 20 kA/cm2. The value of avalanche zone velocity is given by :
6.25 x 107 cm/s
To find the value of the avalanche zone velocity for the given TRAPATT diode, we need to use the relationship between current density (\( J \)), doping concentration (\( N_A \)), charge of an electron (\( q \)), and the avalanche zone velocity (\( v \)). The formula that relates these variables is:
\(J = q \cdot N_A \cdot v\)
Where:
- \(J\) is the current density.
- \(q \approx 1.6 \times 10^{-19} \text{ C}\\) is the charge of an electron.
- \(N_A\) is the doping concentration.
- \(v\) is the avalanche zone velocity.
Given:
- \(N_A = 2 \times 10^{15} \, \text{cm}^{-3}\)
- \(J = 20 \, \text{kA/cm}^2 = 20 \times 10^3 \, \text{A/cm}^2\)
Plug the known values into the equation:
\(20 \times 10^3 = 1.6 \times 10^{-19} \times 2 \times 10^{15} \times v\)
Simplifying the equation to solve for \(v\):
\(v = \frac{20 \times 10^3}{1.6 \times 10^{-19} \times 2 \times 10^{15}}\)
Calculating the right side:
\(v = \frac{20 \times 10^3}{3.2 \times 10^{-4}}\)
\(v \approx 6.25 \times 10^7 \, \text{cm/s}\)
Thus, the avalanche zone velocity of the TRAPATT diode is \(6.25 \times 10^7 \, \text{cm/s}\).
This corresponds to the correct answer: 6.25 x 107 cm/s.
Similar Questions
A PIN diode can not be used as
i. Microwave switch
ii. Microwave mixer
iii. Microwave detectorWhich is correct ?
________ diode is not used as a microwave mixer or detector.
Match the given lists :
List – I (Name of the Device) List – II (Application) a. Diode i. Rectification b. Tunnel diode ii. Microwave switching c. Zener diode iii. An oscillator d. PIN diode iv. Voltage regulation Codes :
An important figure of merit for microwave application of Schottky diode is forward bias cut off frequency fco and is given by :
Assertion (A) : A tunnel diode consists of simple p-n junction mode of degenerate semiconductor. The current voltage characteristics consists of three components and shows the negative differential region over part of the forward characteristics.
Reason (R) : In tunnel diode the p-side is highly doped and n-side is highly doped and also used as detector.
Varacter diodes have the following properties :
A. Junction capacitance varies with bias voltage
B. Junction capacitance varies with time
C. Non linearity of varacter diodes makes them suitable for frequency multipliers
D. Linearity of varactor diode makes them suitable for frequency multipliers.
Choose the correct answer from the options given below:
In a tunnel diode, the degeneracy on the n-side can be expressed as
The static current voltage characteristics of a tunnel diode consist of
(a) Tunneling current and thermal current
(b) Thermal current and excess current
(c) Tunneling current only
(d) Tunneling current, excess current and thermal current
Out of these which are correct ?
Match the following :
List – I List – II a. Gunn diode i. degenerate silicon b. Tunnel diode ii. n-type Ga As c. BJT iii. Silicon d. Diode (P-N junction) iv. \(I_o\left[\exp\left(\dfrac{qV}{kT}\right)-1\right]\) Choose the correct answer from the codes given below:
Assertion (A) : The Gunn diode characteristics shows the region of negative resistance.
Reason (R) : The Gunn diode is made of n-type and p-type degenerate semiconductor.
Select your answer using the codes given below.
Important Questions from Types of Diode
For which of the following diodes when the voltage is increased the current flowing through it decreases?
Which of the following is the main application of Zener diode?
A tunnel diode is
When we tune in any desired station in a radio receiver by rotating the tuning control we vary
Which diode is used as a voltage regulator?
