Physics for Scientists and Engineers
6th Edition
ISBN: 9781429281843
Author: Tipler
Publisher: MAC HIGHER
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Question
Chapter 38, Problem 8P
(a)
To determine
Whether the given statement is true.
(b)
To determine
Whether the given statement is true.
(c)
To determine
Whether the given statement is true.
(d)
To determine
Whether the given statement is true.
(e)
To determine
Whether the given statement is true.
(f)
To determine
Whether the given statement is true.
(g)
To determine
Whether the given statement is true.
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In the fabrication of a p-type semiconductor, elemental boron is diffused a small distance into a solid crystalline silicon wafer. The boron concentration within the solid silicon determines semiconducting properties of the material. A physical vapor deposition process keeps the concentration of elemental boron at the surface of the wafer equal to 5.0 x 1020 atoms boron/cm3 silicon. In the manufacture of a transistor, it is desired to produce a thin film of silicon doped to a boron concentration of at least 1.7 x 1019 atoms boron/cm3 silicon at a depth of 0.20 microns (µm) from the surface of the silicon wafer. It is desired to achieve this target within a 30-min processing time. The density of solid silicon can be stated as 5.0 x 1022 atoms Si/ cm3 solid.
(a) At what temperature must the boron-doping process be operated? It is known
that the temperature dependence of the diffusion coefficient of boron (A) in silicon (B) is given by
Where Do=0.019 cm2/s and Qo=2.74 x 105…
Which statement about the intrinsic carrier concentration in a semiconductor material is FALSE?
The intrinsic carrier concentration is exponentially dependent on the inverse of the temperature of the semiconductor material.
In an intrinsic semiconductor material, the concentration of electrons in the conduction band is equal to the concentration holes in the valence band.
The intrinsic carrier concentration of a semiconductor material at a constant temperature depends on the Fermi energy.
The intrinsic Fermi energy is positioned near the center of the bandgap for an intrinsic semiconductor.
The energy gaps Eg for the semiconductors silicon and germanium are, respectively, 1.12 and 0.67 eV. Which of the following statements, if any, are true? (a) Both substances have the same number density of charge carriers at room temperature. (b) At room temperature, germanium has a greater number density of charge carriers than silicon. (c) Both substances have a greater number density of conduction electrons than holes. (d) For each substance, the number density of electrons equals that of holes.
Chapter 38 Solutions
Physics for Scientists and Engineers
Ch. 38 - Prob. 1PCh. 38 - Prob. 2PCh. 38 - Prob. 3PCh. 38 - Prob. 4PCh. 38 - Prob. 5PCh. 38 - Prob. 6PCh. 38 - Prob. 7PCh. 38 - Prob. 8PCh. 38 - Prob. 9PCh. 38 - Prob. 10P
Ch. 38 - Prob. 11PCh. 38 - Prob. 12PCh. 38 - Prob. 13PCh. 38 - Prob. 14PCh. 38 - Prob. 15PCh. 38 - Prob. 16PCh. 38 - Prob. 17PCh. 38 - Prob. 18PCh. 38 - Prob. 19PCh. 38 - Prob. 20PCh. 38 - Prob. 21PCh. 38 - Prob. 22PCh. 38 - Prob. 23PCh. 38 - Prob. 24PCh. 38 - Prob. 25PCh. 38 - Prob. 26PCh. 38 - Prob. 27PCh. 38 - Prob. 28PCh. 38 - Prob. 29PCh. 38 - Prob. 30PCh. 38 - Prob. 31PCh. 38 - Prob. 32PCh. 38 - Prob. 33PCh. 38 - Prob. 34PCh. 38 - Prob. 35PCh. 38 - Prob. 36PCh. 38 - Prob. 37PCh. 38 - Prob. 38PCh. 38 - Prob. 39PCh. 38 - Prob. 40PCh. 38 - Prob. 41PCh. 38 - Prob. 42PCh. 38 - Prob. 43PCh. 38 - Prob. 44PCh. 38 - Prob. 45PCh. 38 - Prob. 46PCh. 38 - Prob. 47PCh. 38 - Prob. 48PCh. 38 - Prob. 49PCh. 38 - Prob. 50PCh. 38 - Prob. 51PCh. 38 - Prob. 52PCh. 38 - Prob. 53PCh. 38 - Prob. 54PCh. 38 - Prob. 55PCh. 38 - Prob. 56PCh. 38 - Prob. 57PCh. 38 - Prob. 58PCh. 38 - Prob. 59PCh. 38 - Prob. 60PCh. 38 - Prob. 61PCh. 38 - Prob. 62PCh. 38 - Prob. 63PCh. 38 - Prob. 64PCh. 38 - Prob. 65PCh. 38 - Prob. 66PCh. 38 - Prob. 67PCh. 38 - Prob. 68PCh. 38 - Prob. 69PCh. 38 - Prob. 70PCh. 38 - Prob. 71PCh. 38 - Prob. 72PCh. 38 - Prob. 73PCh. 38 - Prob. 74PCh. 38 - Prob. 75PCh. 38 - Prob. 76P
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