Question

The net electron mobility ?n of a semiconductor is a combination of the mobility due to...

The net electron mobility ?n of a semiconductor is a combination of the mobility due to the ionized impurity scattering, which is proportional to T^3/2 , and the mobility due to the lattice scattering, which is proportional to T^-3/2 . For a given semiconductor, the mobility as a function of T is found to be maximal at room temperature T = 300 K. At what temperature the diffusion coefficient Dn is maximal?

Science   Advanced-Physics   
0 0
Add a commentTranscribed image text
Next >

Homework Answers

Answer #1

Mathematical Explanation-

Diffusion coefficient is directly proportional to mobility.lf mobility of a semiconductor is maximum at 300k means diffusion will also be maximum at the same temperature.

Conceptual Explanation-

Mobility is defined as drift velocity per unit applied electric field.More is the mobility means its velocity under applied electric field is more.Means more and more particles can diffuse inside at that temperature hence more will be the diffusion coefficient.

0 0
Know the answer?
Your Answer:

Post as a guest

Your Name:

What's your source?

Earn Coins

Coins can be redeemed for fabulous gifts.

Log In

Sign Up

Not the answer you're looking for?
Ask your own homework help question
Similar Questions
The electron concentration in a semiconductor is given by n = 1016((1-2x)/L) cm-3 for 0 ≤...
The electron concentration in a semiconductor is given by n = 1016((1-2x)/L) cm-3 for 0 ≤ x ≤ L, where L = 15 μm. The electron mobility and diffusion coefficient are μn = 1200cm2/V-s and Dn = 30.9cm2/s. An electric field is applied such that the total electron current density is a constant over the given range of x and is Jn = -50 A/cm2 . (a) Determine the electron diffusion current density (b) Determine the required electric field versus...
The electron concentration gradient of some material is dn/dx=1017cm-4, and the Constant Table: e0 =8.85´10-12C2×N--1×m-2 ;...
The electron concentration gradient of some material is dn/dx=1017cm-4, and the Constant Table: e0 =8.85´10-12C2×N--1×m-2 ; R=8.315J-mol-1×K-1; m0= 4π´10-7N×A-2; h = 6.63´10-34J×s; e = 1.602´10-19C; G=6.67´10-11N×m2-kg-2; me=9.11´10-31kg; g=9.8 m/s2; mobility of the electron is 1350 cm2/V.s，calculate: (a) the diffusion coefficient of the electron, assuming kT=0.0259ev at T = 300 K. (b) the diffusion current density of electrons.
.         Consider a silicon sample at 300 K. Assume that the electron concentration varies linearly with...
.         Consider a silicon sample at 300 K. Assume that the electron concentration varies linearly with distance. At x=0, the electron concentration is n(0). At x=10 µm, the electron concentration is n(10µm)= 5x1014/cm3. If the electron diffusion coefficient, assumed constant, is Dn =30 cm2/sec, determine the electron concentration at x=0 for the following two diffusion current densities: (a) the diffusion current density is found to be Jndiff = + 0.9 A/cm2 and (b) Jndiff = - 0.9 A/cm2.
Consider an n-doped semiconductor with an effective electron mass equal to one half the free electron...
Consider an n-doped semiconductor with an effective electron mass equal to one half the free electron mass, and a dielectric constant of 2. Which of the following statements is correct? More than one is correct A. The impurity will look like a hydrogen atom, but with a hole circling it instead of an electron B. The impurities will look like Hydrogen atoms, but smaller in size than a Hydrogen atom in free space C. The impurity will look like a...
1. Compute the resistivity of an intrinsic semiconductor at 300 K, in units of Ω-m, given...
1. Compute the resistivity of an intrinsic semiconductor at 300 K, in units of Ω-m, given that it has an intrinsic carrier concentration of 4.9 x1022m-3 and electron and hole mobilities of 0.53 and 0.09 m2/V-s, respectively. 2. The intrinsic concentration of electrons and holes (i.e. concentration of e-h pairs) in Si at room temperature is approximately 1x1010 cm-3. Given the density and atomic mass of Si to be 2.33 g/cm3 and 28.06 g/mol, determine the ratio of ionized to...
question about semiconductor devices 1. Why is not a physical mask necessary in electron beam lithography?...
question about semiconductor devices 1. Why is not a physical mask necessary in electron beam lithography? How does the throughput of electron beam lithography compare to UV lithography? 2. What is a plasma, and how can it be formed? What are the advantages, and potential disadvantages, with a plasma-enhanced CVD process? 3. There are three important categories/families of dry etch processes, which are those three? Which one can give the highest anisotropy? 4. Ion implantation is today used for most...
True or False Then provide a brief justification for your answer . 1 Indirect semiconductors are...
True or False Then provide a brief justification for your answer . 1 Indirect semiconductors are best suited for optoelectronic applications (LED, lasers). True or False and Reason : 2 Silicon has four electrons in the outer shell . True or False and Reason : 3 There is strong electric field in the neutral region of a p-n diode . True or False and Reason : 4 Conductivity of n-doped semiconductors decreases at very low temperatures due to low impurity...
#2 At one instantaneous moment, the electron concentration in n-type silicon at 300 K varies linearly...
#2 At one instantaneous moment, the electron concentration in n-type silicon at 300 K varies linearly from 1e17 cm-3 at x = 0 to 6e16 cm-3 at x = 2 µm. Calculate the electron current density in the silicon sample at that moment. Assume µn= 1000 cm2/V/s. #3 Explain why the assumed mobility in question #2, above, is valid and reasonable.  NOTE: I just need to know the 2nd part of the question that why 'mu' = 1000 is valid and...
A. Consider a hydrogen atom with one electron and quantized energy levels. The lowest energy level...
A. Consider a hydrogen atom with one electron and quantized energy levels. The lowest energy level (n = 1) is the ground state, with energy -13.6 eV. There are four states corresponding to the next lowest energy (n = 2), each with energy-3.4 eV. For the questions below, consider one of these four states, called one of the first excited states. 2. Assume that this hydrogen atom is present in a gas at room temperature (T ~ 300 K, kBT...
Consider a silicon diode at T=300 K with Nd = 4 × 1016 cm?3 , Na...
Consider a silicon diode at T=300 K with Nd = 4 × 1016 cm?3 , Na = 1 × 1015 cm?3 , Dn = 25 cm2/s, Dp = 10 cm2/s, ?n = 5 × 10?7 s, ?p = 10?7 s, A = 10?3 cm2 , ni = 1.5 × 1010 cm?3 , r = 11.7. (1) Determine diffusion capacitance and junction capacitance at (a) Va = 0.4 V; (b) Va = 0.6 V. (2) At what voltage the two capacitances...
ADVERTISEMENT
Need Online Homework Help?

Get Answers For Free
Most questions answered within 1 hours.

Ask a Question
ADVERTISEMENT