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A substrate is. a sublayer in MEMS. a flat microscopic object. a flat macroscopic object in microelectronics.

A semiconducting material can be made to become an electrically conducting material by. applying high electric voltage. applying high current. introducing the right kind of foreign atoms into the semiconducting material.

Silicon has a Young’s modulus similar to that of. aluminum. stainless steel. copper.

Silicon has a mass density similar to that of. aluminum. stainless steel. copper.

The principal reason why silicon is an ideal material for MEMS is. its dimensional stability over a wide range of temperatures. it is light and strong. it is readily available.

Silicon has a coefficient of thermal expansion. higher than that of silicon dioxide. lower than that of silicon dioxide. about the same as that of silicon dioxide.

The 300‑mm wafers offer. 2 times more area for substrates than that by 200‑mm wafers. 2.25 times more area for substrates than that by 200‑mm wafers. 2.5 times more area for substrates than that by 200‑mm wafers.

The length of the lattice of a silicon crystal is. 0.543 nanometer. 0.643 nanometer. 0.743 nanometer.

Miller’s indices are used to designate. the length of a face‑centered cubic crystal. the plane of a face‑centered cubic crystal. the volume of a face‑centered cubic crystal.

The (100) plane in a silicon crystal consists of. 5 atoms. 8 atoms. 6 atoms.

The (110) plane in a silicon crystal consists of. 5 atoms. 8 atoms. 6 atoms.

The (111) plane in a silicon crystal consists of. 5 atoms. 8 atoms. 6 atoms.

The growth of silicon crystals is slowest in the. <100> direction. <110> direction. <111> direction.

Silicon conducts heat. 50 times faster than silicon oxide. 150 times faster than silicon oxide. 200 times faster than silicon oxide.

Silicon carbide films are used to protect. the underlying substrates. the integrated circuits. the electric interconnects in a microsystem.

Silicon nitride is. tougher than silicon in strength. weaker than silicon in strength. about the same as silicon in strength.

Pure and single‑crystal silicon. exists in nature. is grown from special processes. is made by electrolysis.

Wafers used in MEMS and microelectronics are. the products of a single‑crystal silicon boule. are synthesized from silicon compounds. exist in nature.

MEMS design engineers are advised to adopt. any size of wafer. a custom‑specified size of wafer. an industrial standard size of wafer.

The total number of atoms in a silicon unit crystal is. 18. 16. 14.

The toughest plane for processing in a single silicon crystal is. the (100) plane. the (110) plane. the (111) plane.

The 54.74° slope in the cavity of a silicon die for a pressure sensor is. determined by choice. a result of the crystal’s resistance to etching in the (111) plane. a result of the crystal’s resistance to etching in the (110) plane.

Polysilicon is popular because it can easily be made as a. semiconductor. insulator. electrical conductor.

Polysilicon films are used in microsystems as. dielectric material. substrate material. electrically conducting material.

The electrical resistance of silicon piezoresistors varies in. all directions. only in the preferred directions. neither of the above applies.

It is customary to relate silicon piezoresistance change to. deformations induced in the piezoresistors in MEMS and microsystems. strains induced in the piezoresistors in MEMS and microsystems. stresses induced in the piezoresistors in MEMS and microsystems.

There are. three piezoresistive coefficients in silicon piezoresistors. four piezoresistive coefficients in silicon piezoresistors. six piezoresistive coefficients in silicon piezoresistors.

The single most serious disadvantage of using silicon piezoresistor is. the high cost of producing such resistors. its strong sensitivity to signal transduction. its strong sensitivity to temperature.

Gallium arsenide has. 6 times higher electron mobility than silicon. 7 times higher electron mobility than silicon. 8 times higher electron mobility than silicon.

Gallium arsenide is chosen over silicon for the use in micro‑optical devices because of its. optical reflectivity. dimensional stability. high electron mobility.

Gallium arsenide is not as popular as silicon in MEMS application because of. its higher cost in production. difficulty of mechanical work. low mechanical strength.

Quartz crystals have the shape of. a cube. a tetrahedron. a body‑centered cube.

It is customary to relate the voltage produced by a piezoelectric crystal to the. deformations. temperature. stresses induced in the crystal.

Application of mechanical deformation to a piezoelectric crystal can result in the production of. electric resistance change in the crystal. electric current change in the crystal. electric voltage change in the crystal.

Most piezoelectric crystals. exist in nature. are made by synthetic processes. are made by doping the substrate.

A polymer is a material that is made up of many. small‑size molecules. large‑size molecules. long‑chain molecules.

In general, polymers are. electrically conductive. semi electrically conductive. insulators.

Polymers. can be made electrically conductive. cannot be made electrically conductive. may never be made electrically conductive.

The LB process is used to produce. thin films. dies. piezoelectric polymers in MEMS and microsystems.

MEMS and microsystem packaging materials are. restricted to microelectronics packaging materials. just about all engineering materials. semiconducting materials.