代写接单辅导-EE5508 Semiconductor Fundamentals (Semester I, AY2023/2024)

欢迎使用51辅导,51作业君孵化低价透明的学长辅导平台,服务保持优质,平均费用压低50%以上! 51fudao.top

Department of Electrical and Computer Engineering National University of Singapore

EE5508 Semiconductor Fundamentals (Semester I, AY2023/2024)

Instructions:

‒ Work on the two assignments and submit a report for each assignment by 31 October 2023.

‒ The report should be uploaded in the “Assignment report” folder in Canvas. The file should be named as: “Your name_ Matriculation Number.*”.

‒ It is important to note that plagiarism is strictly not allowed and will result in zero marks for the assignment.

‒ MATLAB installation:

a) Create your MATLAB account using your NUS email address:

https://www.mathworks.com/mwaccount/

b) Use the direct link to start the software installation:

https://www.mathworks.com/academia/tah-portal/national-university-of-singapore- 31340264.html

Assignment #1

The Fermi level in a non-degenerate Si can be found by solving the following equation:

 E−E N E−E N

Nexp−C F + a

 B  1+4exp− F a   B  1+2exp− d F 

=Nexp− F V+

 kBT   kBT 

d

C kT E−EV kT E−E

      Here, NC (NV) is the effective density of states in the conduction (valence) band, EC (EV) is the energy of conduction (valence) band edge, EF is the Fermi energy, Nd (Na) is the donor (acceptor) concentration, Ed (Ea) is the donor (acceptor) energy level, T is the temperature, and kB is the Boltzmann constant. Once the Fermi level is known, the electron and hole density can be calculated as follows:

n=N exp−EC −EF  and p=N exp−EF −EV  CkT VkT

  B B

• Develop an Excel Spreadsheet for calculating the Fermi level and carrier density (including both electrons and holes) of Si by treating Nd and Na as input parameters. Plot carrier density (in log scale) and Fermi energy (in linear scale) as a function of reciprocal temperature (1000/T) in the range of T = 10 – 800 K. In total, you should have 3 plots: i)

 

log(������) − 1000/������ , ii) log(������) − 1000/������ , and iii) ������������ − 1000/������ . Your Excel Spreadsheet must be able to calculate EF, n and p, and display the results automatically when Nd and Na are changed. If you choose to use Excel, you only need to submit the Excel Spreadsheet for this assignment.

• If you are not familiar with Excel, you may also use Matlab. In this case, submit a report in the form of MATLAB Live Scripts. Your MATLAB live scripts should be able to perform the calculations and show the following results:

i) 3D surface plot and contour lines of ������������(������������, ������������) at (i) T = 100 K, (ii) T = 300 K and (ii) T = 600 K; Range for ������������ and ������������: 1 × 1010������������−3 − 1 × 1019������������−3.

ii) log(������) − 1000/������ , log(������) − 1000/������ , and ������������ − 1000/������ plots for the following dopant concentrations:

������ 17 −3 ������ 5 −3 a) ������ = 10 ������������ , ������ = 10 ������������

b) ������������ = 1015������������−3, ������������ = 105������������−3 c) ������������ = 105������������−3, ������������ = 105������������−3 d) ������������ = 105 ������������−3, ������������ = 1015������������−3 e) ������������ = 105������������−3, ������������ = 1017������������−3

§ You may assume that the donor and acceptor impurities are phosphorous (P) and aluminum (Al), respectively. You may use the following equations and parameters for the calculations:

������������ = 1.17 − 4.73 × 10−4������2/(������ + 636) (T: temperature in unit of Kelvin)

= 2 �������������h�������������������3/2 ������ 2������ħ2 ������ ������ 2������ħ2

������ = 2 ��������������������������������������3/2 ������ , ������

  ������������������ = (������1∗������2∗������3∗)1/3, ������������h = (������∗32 + ������∗32 )2/3, ������1∗ = ������2∗ = 0.19������������, ������3∗ = 0.98������������, ������h hh

������∗ =0.16������ , ������∗ =0.49������ , ������ =6,������ =9.109×10−31kg ������h ������ hh ������ ������ ������

 Ionization energy of phosphorous in Si: 0.045 eV Ionization energy of aluminum in Si: 0.067 eV

For your reference, for P-doped Si with ������������ = 1015������������3, ������������ = 0, the log(������) − 1000/������ plot may look like the following:

 

 Assignment #2

Semiconductor superlattices (SLs) are artificial structures composed of alternating layers of two semiconductors with similar lattice structure but different bandgaps. Leo Esaki's theoretical work in the 1970s laid the foundation for understanding quantum confinement effects and the associated electronic properties of these low-dimensional structures. Since its first experimental realization in the GaAs/AlAs system, the SL has grown to encompass a wide variety of material systems, including elemental and compound semiconductors, and more recently 2D materials. These materials not only provide a good platform for studying quantum confinement effects in low- dimensional structures, but also have unique applications that cannot or difficult to be realized by bulk semiconductors. One of these applications is quantum cascade lasers (QCLs). Unlike typical semiconductor lasers that emit light through electron–hole recombination across the band gap, the QCLs are unipolar, and lasing is achieved through inter-subband transitions in a repeated stack of quantum wells and superlattices. The wavelength of QCL can be tuned in the mid- to far-infrared range of the electromagnetic spectrum, making it ideal for many applications requiring long- wavelength lasers.

Do a literature review and write a report on QCLs. Your report should cover brief history, basic principles of operation, typical material systems and fabrication methods, applications, and future outlook of the QCL technology.

Prepare your report within 10 A4 pages in 12pt Time New Roman font and 1.5 line spacing, including figures and references.

 

 

51作业君

Email:51zuoyejun

@gmail.com

添加客服微信: abby12468