Materials Science Quiz on Thin Film Growth

<p>Lower temperatures result in lower conductivity while increased temperatures raise conductivity. (B)</p> Signup and view all the answers

<p>An imaginary energy level where electrons are located at a certain temperature. (C)</p> Signup and view all the answers

<p>$a = b \neq c$ and $α = β = γ = 90°$ (C)</p> Signup and view all the answers

<p>Face-centered cubic (B)</p> Signup and view all the answers

<p>8 (B)</p> Signup and view all the answers

<p>6 (D)</p> Signup and view all the answers

<p>$a \neq b \neq c$, $α\neq β\neq γ$ (C)</p> Signup and view all the answers

<p>CsCl (B)</p> Signup and view all the answers

<p>4 (A)</p> Signup and view all the answers

<p>Between 0.9 and 1.0 (B)</p> Signup and view all the answers

<p>4 (C)</p> Signup and view all the answers

<p>They are polymorphs, with graphite being thermodynamically more stable than diamond. (C)</p> Signup and view all the answers

<p>M(s) → M(g) (A)</p> Signup and view all the answers

<p>Aluminum (Al) ions in octahedral holes within a hexagonal close-packed (hcp) array of oxygen (O) ions. (C)</p> Signup and view all the answers

<p>The sum of ionization energies for the metal in its gaseous state. (A)</p> Signup and view all the answers

<p>sp² (D)</p> Signup and view all the answers

<p>Na(s) + 1/2 H₂(g) → Na(g) + H(g) → NaH(s) (D)</p> Signup and view all the answers

<p>(A*, B²⁺, O) (D)</p> Signup and view all the answers

<p>NaCl (C)</p> Signup and view all the answers

<p>γ-alumina is less dense and has a more open structure compared to α-alumina. (B)</p> Signup and view all the answers

<p>It provides a method for estimating the lattice energy of an ionic compound. (A)</p> Signup and view all the answers

<p>Born exponent, related to the repulsion between ions. (B)</p> Signup and view all the answers

<p>m (C)</p> Signup and view all the answers

<p>It is a face-centered cubic (fcc) array of anions with cations occupying tetrahedral and octahedral holes. (B)</p> Signup and view all the answers

<p>Magnesium (Mg) (A)</p> Signup and view all the answers

<p>To grow thin films with smooth surfaces. (C)</p> Signup and view all the answers

<p>To absorb blue light and convert it into a mixture of yellow, green, and blue light. (D)</p> Signup and view all the answers

<p>Production of optoelectronic devices (C)</p> Signup and view all the answers

<p>From the p-type to the n-type material. (C)</p> Signup and view all the answers

<p>450 nm (C)</p> Signup and view all the answers

<p>It prevents the flow of charge carriers across the junction. (C)</p> Signup and view all the answers

<p>The band gap becomes larger. (B)</p> Signup and view all the answers

<p>An electron returns to the valence band, releasing a photon. (D)</p> Signup and view all the answers

<p>Their quantized energy levels lead to narrow emission but can absorb a wide range of wavelengths (B)</p> Signup and view all the answers

<p>The energy increases resulting in a shorter wavelength. (C)</p> Signup and view all the answers

<p>To convert light into specific wavelengths by absorbing high-energy photons (A)</p> Signup and view all the answers

<p>The smaller the size of 'a' the higher the confinement energy. (D)</p> Signup and view all the answers

<p>It modifies their electronic and optical properties for tailored colours. (B)</p> Signup and view all the answers

<p>The additional energy a particle has due to its confinement within the quantum dot. (B)</p> Signup and view all the answers

A classification of crystal lattices into seven distinct types based on symmetry and dimensions.

The dimensions of a unit cell in a crystal lattice, described by edges 'a', 'b', 'c' and angles 'α', 'β', 'γ'.

A crystal system where all sides are equal and angles between them are 90°.

A lattice type where 'a' and 'b' are equal but differ in 'c' with all angles at 90°.

A type of crystal lattice with an atom in the center of the cube and atoms at each corner.

A crystal structure represented by the formula ABO3, where A and B are different cations.

The number of nearest neighbors surrounding an atom in a crystal structure.

A measure used to determine the stability of perovskite structures based on ionic sizes.

The process of growing a crystalline layer on a substrate with a similar crystal structure.

A technique using self-limiting reactions to deposit thin films one layer at a time.

The energy difference between the valence band and the conduction band in semiconductors.

An imaginary marker indicating the energy levels of electrons in a material at a given temperature.

When the crystal structure of one material aligns with another to allow for epitaxy.

Doping GaN with magnesium to create positive charge carriers (holes).

Doping semiconductor (GaN) with silicon or other group 2 or 4 elements to create negative charge carriers (electrons).

Current flows from the positive side to the negative side, resulting in light emission.

No light emission occurs as current flows from negative to positive, preventing charge carrier movement.

When blue light hits this phosphor, it absorbs and re-emits light as a mixture perceived as white light.

Heat required to convert one mole of solid metal M(s) to gaseous metal M(g).

Heat required to convert one mole of molecular X2(g) to individual atoms X(g).

Total energy needed to remove electrons from gaseous metal M(g) to form M²+(g).

Energy released when gaseous ions form an ionic solid MX(s).

The ΔH change when one mole of a compound is formed from its elements in their standard states.

Formula to calculate potential energy between two charged ions based on their distance and charge.

Process of depositing thin films on a substrate using gas-phase chemical reactions of precursors.

Compounds used in CVD that combine metal with organic components for thin film deposition.

Hardest natural substance with a covalent bond and tetrahedral coordination (CN=4).

Carbon structure with sp² hybridization, known for conductivity and layer formation.

Crystal structure of ZnS with face-centered cubic (FCC) topology and tetrahedral holes.

Hexagonal polymorph of ZnS with a similar structure to zinc blende.

A crystal structure made of Al2O3, extremely hard; forms rubies and sapphires.

γ-Al2O3, a less dense, more reactive form of Al2O3 with an open structure.

Energy required to break ionic compounds into gaseous ions.

Nanoscale semiconductor particles that confine electrons and holes in a small region, leading to discrete energy levels.

The process where a photon moves an electron from the valence band to the conduction band, creating an electron-hole pair.

The process where electrons recombine with holes, releasing energy in the form of light (photon).

The ability of quantum dots to emit light at varying wavelengths depending on their size.

The additional energy required for particles confined in quantum dots, contributing to their unique properties.

Semiconductor nanocrystals used to convert light into specific wavelengths, often combined with traditional phosphors.

Semiconductor nanocrystals modified with phosphors to enhance optical properties and reduce defects.

Quantum dots can absorb a wide range of light but emit a narrow peak, resulting in pure colors.