All RF Cafe quizzes would make perfect fodder for employment interviews for technicians or engineers
- particularly those who are fresh out of school or are relatively new to the work world. Come to
think of it, they would make equally excellent study material for the same persons who are going to
be interviewed for a job.Some of these books used in quizzes
are available as prizes in the monthly
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Note: Many answers contain passages quoted from the text.
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quiz is based on the information presented in Advanced RF MEMS, by Stepan Lucyszyn. This book is full of
cool micrographs of actual device geometries.
Cambridge University Press is the publisher. Note: Some of these books are
available as prizes in the monthly RF Cafe
1. What does the acronym MEMS stand for?
b) Microelectromechanical Systems
2. Which material is commonly used in RF MEMS for its
superior magnetic and thermal
c) Electroplated nickel
years, electroplated nickel has been used as a structural material in microfabricated
circuits, RF MEMS
switches and antennas. Its thermal expansion coefficient is 5x that of
polycrystalline silicon. (see page
3. What distinguishes MEMS devices from traditional integrated circuits?
d) Physical displacement of internal components
Moveable, three-dimensional physical structures are
created to perform mechanical functions.
4. Which properties of a MEMS RF switch are
superior to a solid state RF switch?
a) Insertion loss and bandwidth
In some aspects, such as power consumption,
loss and bandwidth,
RF MEMS switches have and advantage over
electronic PIN diode and FET devices.
(see page 37)
5. Which properties of a MEMS RF switch are
inferior to a solid state RF switch?
b) Speed and size
The response time of RF MEMS switches is
much longer than that of electronic switches.
(see page 37)
What is the purpose of a sacrificial layer during MEMS fabrication?
d) Allows dry etching to reduce
undercutting and erosion common with wet etching
Dry etching of with an oxygen plasma allows high
selectivity when removing materials.
(see page 63)
application would be perfect for multi-pole, multi-throw MEMS RF switch?
d) All the above.
(see page 90)
8. What is the purpose of a "hold electrode?"
a) To counter induced bias from a
strong RF signal power level
As a way of avoiding self-actuation, through an excess in the mean RF signal
a number of switches designs have incorporated a second hold electrode, in addition to
the normal pull-down electrode. (see page 95)
9. Which phenomenon is
possible in a MEMS device but not in a solid state device?
a) Vibration-induced actuation
Self-actuation can occur due to vibration or shock. (see page 129)
is zero-level (0-level) packaging?
c) On-wafer encapsulation
Zero-level packaging creates an
on-wafer, device-scale, enclosure (or sealed cavity for) the
MEMS, serving as the first protective
interface. (see page 233)