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Flashcards in QE12 Deck (10):
1

Which of the following wet silicon etchants have the best p++ stop selectivity?

EDP

2

Gas phase isotropic silicon etch is frequently used to release microstructures such as cantilever beams, what is the most common dry etch used for this purpose?

XeF2 or BrF3

3

Name two of the biggest commercial markets for silicon inertial sensors.

Accelerometer, gyroscope

4

Evaporation and sputtering are two common metallization methods used in MEMS and microfabrication, name two advantages of sputtering.

Sputtering has the advantage of high density coatings (higher energy), no need for low vacuum level

5

Name two advantages of flip chip bonding as compared to wire bonding.

1. Can have sensitive magnetic instruments in flip chip bonding
2. Allows for wafer level integration.

6

Name two substrate bonding methods that can create a hermetic seal for a sensor that has to operate in liquid environment.

1. Solder bonding
2. Mechanical bonding

7

Which one has a higher Young's modulus, silicon or aluminum?

Silicon

8

What is the name of a very popular polymer that can be deposited at low temperatures, is biocompatible, and has conformal coating. This polymer is used extensively in medical microdevice passivation and coating among other things.

Parylene

9

Most physiological signals have a low frequency spectrum (9-100Hz). Name one that is probably the highest (20,30 kHz).

Hearing

10

Why do we use Ag/AgCl electrodes in most electrochemical measurements?

Degradation