Seite 1 von 1


Verfasst: 25.07.2016 11:04
von MisterGoetze
Hello, this is my list of the today's questions of the exam "3D Integration" by Prof. Iuliana Panchenko.
  • A figure was shown and you had to determine if it was 2.5D or 3D integration. Furthermore was asked to describe 2.5D and 3D integration.
  • Via First: Which materials can be used as filling materials (name 3); which material would you use for filling if yuo have a via first process (and why)?
  • DRIE: decribe BOSCH process (with sketches); which parameters have an impact on the etch rate? And a figure was shown in which you have to explain why larger TSV diameters cause deeper TSV lengths.
  • WET and LASER: What is the first step of wet etching? Name 3 advantages and disadvantages of LASER drilling.
  • Thin-film: sketch a CVD chamber. which materials are used for a barrier layer? Why is magnetron sputtering better than conventional sputtering?
  • Via Filling: which materials can be used to fill a via? write down the chemical reactions at cathode and anode.
  • Metallization: Sketch RDL Cu line process. Why is copper a very good material to use?
  • Bonding/ Debonding: Describe chemical debonding and bonding techniques. Name the materials of carrier and adhesive. Why is a high TTV not good for further processing? Name Quality parameters.
  • Grinding: Describe the DBG process. Name the aims of the stress relief and you want to etch 20um in 1 min - which stress relief technology do you use?
  • Bonding: what is the difference between direct and indirect bonding? Name 2 examples each. Describe the SLID bonding. (figure was given and you had to name the different components).
  • Which technological parameters have to be considered for fine-pitch bonding (6)-
  • Cu TCB: Name 4 advantages of Cu TCB. How can you even improve this process?
  • Metrology: 3 different cases were given and you should say which technology might be the best for analysis.
  • Something to nanoporous connections (formation).
All in all it was arounf 80 points to achieve. If you are prepared properly it is not that big of a deal. The list above does NOT contain all questions. There are some more.

Re: Klausuren

Verfasst: 17.02.2017 11:39
von MisterGoetze
Here the list of the questions of the second part of the module by Prof. Iuliana Panchenko (Micro- and Nanomaterials and reliability aspects).
  • Methods for material characterisation: Name at least 2 different methods for imaging, spectroscopy, lattice and bulk technology. Explain how an EDX works.
  • You have a Sn-solderball and you want to inspect its microstructure. Which method do you have to apply first when you have the whole package (x-sectioning). How can you determine lattice parameters. name to different technologies and at least one advantage and disadvantage.
  • Crystallography: A picture with 3 different planes was given. Determine the Miller Indices. And additionally 3 vectors were given and you had to determine the crystal direction (mind the different brackets!). Write down the relations of a, b and c (and the angles) for cubic, tetragonal, hexagonal and monoclinic unit cells.
  • Four pictures with different defects were given and you had to determine which is which. ...
  • Draw Edge-Dislocation and mark Burgers-Vektor, ds and Gilde plane. What connection does b and ds have for a screw dislocation?
  • Pb-Sn-Phase diagram which determination of fractions of the different parts (exactly like in the lecture!).
  • Calculation of Schmidt factor and glide planes.
  • High temperature treatment of materials (explan recovery and recrystallization, ...)
  • What is the charcteristic lifetime? Draw the bathtub curve and give the values for the shape parameter b.
  • Nanomaterials: Why are nanomaterials more likely to intereact with their environment? You have 2nm and 10 nm nanoparticle - you want to lower the sintering temperature: which one do you use? How can you use magnetic fields for nanomaterials applications? Explain.

So, all in all 10 questions. You have to be very fast to get everything done in 90 minutes - so do at first the questions you are sure with.