Deposition

Question 1

3D-LSI

Answer 1

3D Integrated Circuit; Large-Scale Integration

Question 2

step coverage

Answer 2

• The ratio of thickness of film along the walls of a step to the thickness of the film at the bottom of a step.
• Good step coverage reduces electromigration and high-resistance pathways.
• Also improves gap-filling

Question 3

CVD

Answer 3

Chemical Vapor Deposition

• Deposition occurs as a byproduct of a chemical reaction in vapor phase.
• Most common thin film deposition method in advanced semiconductor manufacturing

Question 4

PVD

Answer 4

Physical Vapor Deposition

Deposition occurs as a byproduct of a physical process such as, evaporation from a source followed by condensation on another surface.

Question 5

Resistivity (Volume)

Answer 5

• The resistance that a unit volume of a material offers to the passage of electricity, the electric current being perpendicular to two parallel faces.
• More generally, the volume resistivity is the ratio of the potential gradient parallel with the current in the material to the current density.

Question 6

Wafer

Answer 6

• Thin (thickness depends on wafer diameter, but is typically less than 1 mm), circular slice of single-crystal semiconductor material cut from the ingot of single crystal semiconductor
• Used in manufacturing of semiconductor devices and integrated circuits; wafer diameter may range from 25 mm to 300 mm

Question 7

APCVD

Answer 7

Atmospheric Pressure CVD
- Process of chemical vapor deposition carried out at atmospheric pressure

• Typically results in the inferior film quality and conformality of coating as compared to Low Pressure CVD (LPCVD).

Question 8

LPCVD

Answer 8

Low Pressure CVD
- Chemical vapor deposition process carried out at reduced pressure; improves conformality of coating and purity of the films as compared to atmospheric pressure CVD

Question 9

MOCVD

Answer 9

Metal-Organic Chemical Vapor Deposition
- CVD process which uses metal-organic compounds as source materials

• Metal-organics thermally decompose at temperatures lower than other metal containing compounds
• Method often used in epitaxial growth of very thin films of III-V semiconductors.

Question 10

III-V materials

Answer 10

• A substance that can act as an electrical conductor or insulator depending on chemical alterations or external conditions.
• Examples are silicon, germanium, and gallium arsenide

Question 11

III-V device

Answer 11

• An electronic device (e.g. a transistor, diode, or integrated circuit) manufactured from semiconductor materials.
• Semiconductor devices control and amplify because a small voltage or current, or a physical stimulus (such as light or pressure), allows the semiconductor to pass or block electrical current.
• Devices can be fabricated with other capabilities such as passing electric current in only one direction, emitting light, mixing and transforming signals, etc.

Question 12

passivation

Answer 12

• Refers to a material becoming “passive,” that is, being less affected by environmental factors such as air and water.
• Passivation involves a shielding outer-layer of base material, which can be applied as a microcoating, or oxidation which occurs spontaneously in nature.
• As a technique, passivation is the use of a light coat of a protective material, such as metal oxide, to create a shell against corrosion.
• Passivation can occur only in certain conditions, and is used in microelectronics to enhance silicon.[1]
• The technique of passivation is used to strengthen and preserve the appearance of metallics.

Question 13

TEOS

Answer 13

Tetraethyl Orthosilicate, Si(OC2H5)4

• Gaseous compound commonly used in CVD of SiO2 processes (so-called “TEOS Oxide”)
• Good conformality of coating; relatively inert material, liquid at room temperature
• Thermally decomposes at around 700 C to form SiO2
• Plasma enhancement lowers temperature of deposition to below 500 C.

Question 14

LS-CVD

Answer 14

Liquid Source Chemical Vapor Deposition

• SAMCO’s LS-CVD (Liquid Source CVD) systems achieve superior step-coverage and gap-fill performance
• Required for the MEMS, 3D-LSI, and Opto Electronics markets.
• Importantly, the technology enables deposition at lower temperatures and doesn’t require toxic or flammable gases.
• LS-CVD systems can deposit high-quality TEOS-SiO2, LS-SiN, High-k think film, and Diamond-like-carbon (DLC).

Question 15

LS SiN

Answer 15

low stress silicon nitride

Question 16

Å

Answer 16

angstrom (unit of measurement)

Question 17

μm

Answer 17

micrometer

Question 18

refractive index

Answer 18

Determines how much light is bent, or refracted, when entering a material.

Question 19

ø

Answer 19

diameter

Question 20

SiOxNy

Answer 20

silicon oxy-nitride

Question 21

α-Si:H

Answer 21

amorphous silicon

Question 22

PECVD

Answer 22

Plasma Enhanced Chemical Vapor Deposition

- designed for the deposition of insulation and passivation films.

Question 23

dopant

Answer 23

• element introduced into semiconductor to establish either p- type (acceptors) or n- type (donors) conductivity.
• common dopants in silicon: p-type, boron, B; n-type phosphorous, P, arsenic, As ,antimony, Sb.

Question 24

doping

Answer 24

• introduction of dopant into semiconductor for the purpose of altering its electrical properties.
• allows control of resistivity/conductivity of semiconductor by several orders of magnitude.
• also used to convert p-type material into n-type material and vice versa.