1. What is a disadvantage of MEMS? Lower power requirements Greater functionalit
ID: 1767150 • Letter: 1
Question
1. What is a disadvantage of MEMS?
Lower power requirements
Greater functionality per unit space
Accessibility to regions that are forbidden to larger products
In most cases, smaller products should mean lower prices because less material is used
None of the above
2. What is untrue about MEMS-based sensors
A sensor is a device that detects or measures some physical phenomenon such as heat or pressure
Most microsensors are fabricated on a silicon substrate using same processing technologies as those used for integrated circuits
Microsensors have been developed to measure force, pressure, position, speed, acceleration, temperature, flow, and various optical, chemical, environmental, and biological variables
None of the above
All of the above
3. What is untrue about MEMS-based actuators?
An actuator converts a physical variable of one type into another type, and the converted variable usually involves some mechanical action
An actuator causes a change in position or the application of force
Examples of microactuators: valves, positioners, switches, pumps, and rotational and linear motors
All of the above
None of the above
4. MEMS can be fabricated using
LIGA process
Microfabrication
Micromachining
All of the above
None of the above
5. Pressure sensor cannot be designed with
Electrostatic signaling
Electron field emission mechanism
Piezoelectric mechanism
Piezo- resistance mechanism
None of the above
6. What is impossible material choice for MEMS?
Polymer
Silicon
Alumina
Titanium
None of the above
8. If you want to fabricate the following component using negative resist, what will be the right mask?
10. Thickness of photoresist depend on
Viscosity
RPM of spin coater
Wetting properties of substrate
Duration of rotation
None of the above
11. What is the wrong statement?
Wafer prime step is important to clean the substrate
Substrate heating temperature does affect resist thickness
Negative resist can be cleaned with acetone
Prior to develop, resist patterns may be baked
exposure time is less critical in lithography
12. What do you expect in soft bake process?
polymerization, evaporation of solvent, formation of crosslink among resist materials, improvement of adhesion
Oxidation of top layer of resists
Removal of water vapor from resist
Formation of uniform layer by convection air flow in oven
None of the above
For the question 13 through 15, please use the following picture
13. In appropriate exposure (write the picture number such as a, b, c, d,)
14. Over developed
15. Under developed
16.Piezoelectric pressure sensors measure
a. voltage
b. resistance
c. length
d. current
e. nothing, so cannot be used for sensing.
17. MEMS-based diaphragm pressure sensor can be fabricated using
piezoelectric material
piesoresistive material
capacitive based
acoustic wave based
insulator material
18. Thermal properties of material can be used to fabricate
Actuators
Sensors
Thermocouples
Heaters
None of the above
All of the a, b, c, and d
19. Select the wrong statement
Functionalization of cantilever beams can be used to detect biomoleculs
Funtionalizoation of optical waveguide beams used to detect biomolecules
Surface acoustic waves can be used to detect molecules
None of the above method can be used to detect molecules
20. Select a MEMS component that essentially have electrostatic actuation?
Comb drive
Pressure sensor
Waveguide device
Surface acoustic wave detector
Thermal actuator
21. If a capacitor-based MEMS actuator has capacity of 15 Pf and plate distance is 2 micron, what is the force generation, in nN, when 5 V is applied across the capacitor?
a. 17520 nN,b. 1875 nN,c. 1526 nNd. 1578 nN
22. What is the width of opening of SiN layer
55
59
72
85
For questions 23 -25, use following diagram
what is the orientation of Si wafer and etching solution to get (a)
a. Si (111), HF+HNO3
b. Si (110), KOH + Isoprpyl alcohol
c. Si (111), TMAH
d. Si (111) and Plasma
e. Si (100), KOH + Isoprpyl alcohol
what is the orientation of Si wafer and etching solution to get (b)
a. Si (111), HF+HNO3
b. Si (110), KOH + Isoprpyl alcohol
c. Si (111), TMAH
d. Si (111) and Plasma
e. Si (100), KOH + Isoprpyl alcohol
what is the orientation of Si wafer and etching solution to get (c)
a. Si (111), HF+HNO3
b. Si (110), KOH + Isoprpyl alcohol
c. Si (111), TMAH
d. Si (111) and Plasma
e. Si (100), KOH + Isoprpyl alcohol
26. Photoresist can be removed with
acetone
oxygen plasma
H2O2+ H2SO4
phenol
none of the above
27. Select the material that cannot be deposited by CVD process
polysilicon
silicon nitride
crystal silicon
silicon oxide
all of the above
28. The material that rarely used (almost never) for the metallization of MEMS devices,
aluminum
copper
gold
chromium
iron
29. Most commonly used membrane (diaphragm) materials for MEMS such as pressure sensors
Si
SiN
SiO2
Al2O3
Chromium
30. In the characterization of 3-D MEMS, the following technique has limitation
scanning tunneling microscopy
atomic force microscopy
optical microscopy
all of the above
none of the above
Explanation / Answer
1. none of abive is a disadvantage of mems.
2.none of above is untrue about mems.
3.none of above is untrue about mems.
4.all of above can be used to fabricate mems.
Related Questions
Navigate
Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.