{[ promptMessage ]}

Bookmark it

{[ promptMessage ]}

quz1E_sol_corrected

# quz1E_sol_corrected - Ans type n cm p n n o i o − ⇒ = =...

This preview shows pages 1–2. Sign up to view the full content.

ECE 440: Quiz Section E (1:00 p.m.) Name:_______________________________ 1. (a) For a III-V binary compound semiconductor (zinc-blende), the lattice constant is L in the unit of Angstrom. What is the minimum inter-atomic distance in this material? (2 points) Ans: The zinc-blende lattice is almost identical to the FCC lattice except that there is an additional interpenetrating FCC structure that is translated by (¼, ¼, ¼) x L. Thus, the minimum inter-atomic distance will be L L L L 4 3 4 1 4 1 4 1 2 2 2 = + + (b) Calculate the volume density (atoms/cm 3 ) of the column V atoms in the material. (3 points) Ans: There is 4 column V atoms in each unit cell with length L in the unit of Angstrom). So, density = 4 / ( L × 10 -8 ) 3 = 4 × 10 24 / L 3 (atoms/cm 3 ) 2. The hole concentration in InAs at T = 300 K is p 0 = 1 x 10 13 cm -3 and the intrinsic carrier concentration is 10 15 cm -3 . (a) Is this material n-type or p-type? (1point)

This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document
This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: Ans: ( ) ( ) type n cm p n n o i o − ⇒ = = = − 3 17 13 2 2 10 10 10 15 (b) Sketch the band diagram of the sample, cal culating and labeling the difference between the various energy levels ( E C , E V , E F , E i ). (3points) Ans: (c) Is the probability of finding an electron at the energy level E = E C closer to zero or one? (1 point) Ans: According to Fig. 3-15, the probability is closer to “zero”. 3. On the energy diagram shown below: (a) Among electrons (1), (3) and (4), which one or ones has the highest total energy? (2 points) Ans: According to the diagram, Electron (3) has the highest total energy. (b) Rank the electrons (1), (3), and (4) in descending order of their kinetic energy. (3 points) Ans: Electron (4), (3), (1) in descending order (1) (3) (4) (1') (3') (4') E F x 1 x 2 x 3 x 4 x 5 X E c E v E i E F E g E g /2 Total Electron Energy E Kinetic Energy...
View Full Document

{[ snackBarMessage ]}

### What students are saying

• As a current student on this bumpy collegiate pathway, I stumbled upon Course Hero, where I can find study resources for nearly all my courses, get online help from tutors 24/7, and even share my old projects, papers, and lecture notes with other students.

Kiran Temple University Fox School of Business ‘17, Course Hero Intern

• I cannot even describe how much Course Hero helped me this summer. It’s truly become something I can always rely on and help me. In the end, I was not only able to survive summer classes, but I was able to thrive thanks to Course Hero.

Dana University of Pennsylvania ‘17, Course Hero Intern

• The ability to access any university’s resources through Course Hero proved invaluable in my case. I was behind on Tulane coursework and actually used UCLA’s materials to help me move forward and get everything together on time.

Jill Tulane University ‘16, Course Hero Intern