Manufacturing Processes

Between wire-sawing and ID sawing, which one yields more wafers per unit length of crystal ingot? (A) Wire sawing. (B) ID sawing

A

Flank wear occurs on _______________. (A) the tool face that interacts with the newly-generated chip (B) the tool face that interacts with the newly-generated surface of workpiece

A

Generally speaking, a tool with a negative rake angle is _______ than a tool with a positive rake angle. (A) stronger (B) weaker

A

IC Fabrication involves five general stages. Crystal growing is in the stage of _________ (A) Wafer preparation (B) Wafer fabrication. (C) Wafer test/sort (D) Assembly and packaging. (E) Final test

A

In a turning operation, if the initial diameter minus the final diameter equals 2 mm, what is the dept of cut? (A) 1 mm. (B) 2 mm. (C) 4 mm

A

In drilling operation with a standard twist drill, the cutting speed is different along the cutting lips and the chisel edge. Usually, the speed at the drill center is ________ than that at the outer diameter of the drill. (A) lower (B) higher

A

In machining processes, the newly-generated workpiece surface is too rough. You are suggested to check whether this issue is related to tool wear. So you want to check ______. (A) Flank wear (B) Crater wear

A

Milling is the most popular machining process to produce flat surface.

A

Slab milling is also called peripheral milling.

A

The orientation of silicon wafer is determined in which step? (A) Crystal growth (B) Boule shaping (C) Slicing (D) Lapping

A

An abrasive slurry is used in _________. (A) rotary ultrasonic machining (RUM). (B) ultrasonic machining (USM)

B

In IMSE250, you have seen the applications of the processes below in semiconductor manufacturing except _____. (A) Casting (B) Forming (C) Machining (D) Joining

B

Resistance welding is primarily used for welding ____. (A) Round (bar) metals (B) sheet metal

B

Silicon wafers are about 800 microns thick. Most semiconductor processes occur in the top _____ of a silicon wafer. (A) 0.5 microns (B) 5 microns (C) 50 microns (D) 500 microns

B

The tool vibrates but does not rotate in ___________. (A) rotary ultrasonic machining (RUM). (B) ultrasonic machining (USM)

B

If you already know that the warp of wafer A is larger than the warp of wafer B, the flatness of wafer A should be _______ the flatness of wafer B. (A) larger than (B) smaller than (C) larger or smaller than

C

In milling, if you increase cutting speed, MRR will be ______ (A) Increased (B) Decreased (C) Remaining the same

C

In regard to EBM (electron beam machining), LBM (laser beam machining), and PBM (plasma beam machining), which one of the following is NOT true? (A) They all use their beam to melt the workpiece material. (B) They all cause HAZ (heat-affected-zone). (C) They all require the workpiece material to be electrically conductive (D) They all have some problems if the workpiece is too thick.

C

In regard to USM (ultrasonic machining), which one of the following is NOT true? (A) USM employs an abrasive slurry. (B) In USM, the tool forms a reverse image in the workpiece. (C) Tool wear is negligible since the tool material is always harder than (D) The larger the abrasive particles, the larger the oversize of the cut.

C

In turning process, the tool life is mainly determined by ____. (A) Toughness (B) Young's modulus (C) Hardness

C

Welding _______ requires that the temperature be high enough to melt the part material. (A) always (B) never (C) sometimes

C

Which one of the following orders represents the surface roughness order (from the roughest to the smoothest) generated by these processes? (A) Honing > Reaming > Drilling. (B) Reaming > Drilling > Honing. (C) Drilling > Reaming > Honing. (D) Drilling > Honing > Reaming

C

EDM (Electrical Discharge Machining) has several benefits. Which one of the following is NOT among these benefits? (A) No cutting forces. (B) Burr-free edges. (C) Intricate (complex) details can be cut. (D) The tool never wears

D

In regard to CHM (chemical machining), which one of the following is NOT true? (A) The nature of metal removal is the same as in corrosion of a metal. (B) A mask is sometime used to protect areas not to be etched. (C) CHM induces no stresses. (D) The homogeneity of the material makes no difference

D

In the front-end process, ___________ is used to obtain a flat surface. (A) Deposition. (B) Plasma etching. (C) Photolithography. (D) Chemical-mechanical polishing (CMP)

D

Which one of the following is NOT among the limitations of EDM? (A) Low material removal rate. (B) Long lead time (to prepare the tool). (C) Workpiece materials must be conductive. (D) Can cut only one hole at a time

D

Which one of the following is NOT among the limitations of EDM? (A) Low material removal rate. (B) Long lead time (to prepare the tool). (C) Workpiece materials must be conductive. (D) Can cut only one hole at a time

D

Generally speaking, down milling produce continuous chips but up milling produces interrupted chips

False

Generally speaking, down milling requires higher clamping force than up milling.

False

Generally speaking, smaller rake angle of cutting tool can reduce cutting force in machining processes.

False

In turning process, chip formation is greatly affected by cutting tool material.

False

The temperature should be always high enough to melt the part material in all welding processes.

False

Diamond grinding wheels could be used to grind cutting tools. Is it appropriate to use diamond grinding wheels to grind the cutting tools made of high speed steels?

No

Cold forming can increase the yield strength of workpiece.

True

In turning process, chip formation is greatly affected by cutting speed.

True

The load stress in bending should be somewhere between the yield strength and tensile strength.

True

The working mechanism of etching process is the same as corrosion.

True

Diamond grinding wheels could be used to grind cutting tools. Is it appropriate to use diamond grinding wheels to grind the cutting tools made of tungsten carbides?

Yes