Electrical conductivity and its converse, electrical resistivity, is a fundamental property of a material that quantifies how Germanium conducts the flow of electric current. This is the case in the most conductive metals, such as silver, gold, and copper. There are cool facts about Germanium that most don . Phys. germanium), conductivity increases with temperature over a wide range. The temperature dependence of electrical conductivity of single-crystal and polycrystalline high-purity germanium (HPGe) samples has been investigated in the temperature range from 7 to 100 K. The conductivity versus inverse of temperature curves for three single-crystal samples consist of two distinct temperature ranges: a high-temperature range where the conductivity increases to a maximum . When, ni at 300K = 2.5 1013 /cm and n and p in germanium are 3800 and 1800 cm2/Vs respectively. Thus, EGO is equal to 0.785 (1.21) eV for Ge (Si). The thermal conductivity of nonmetallic liquids generally decreases with increasing temperature. Light gases, such ashydrogenandheliumtypically havehigh thermal conductivity. NS-21, 273 (1974), G. Yang, G.J. Their contribution to the thermal conductivity is referred to as theelectronic thermal conductivity, ke. Dense gases such as xenon and dichlorodifluoromethane have low thermal conductivity. 531, 490 (1982), J.Y. As a solid is heated, itsparticles vibrate more rapidlyas the solid absorbs kinetic energy. Google Scholar, E.E. Vickers Hardness: converted from Mohs scale. Gang Yang. As was written, in liquids, the thermal conduction is caused by atomic or molecular diffusion, but physical mechanisms for explaining the thermal conductivity of liquids are not well understood. Whereas in the case of conductors, when the temperature increases its resistivity increases as electrons collide more frequently with vibrating atoms. The effect of temperature, pressure, and chemical species on thethermal conductivityof a gas may be explained in terms of thekinetic theory of gases. The melting point of ice is 0 C. Cavity walls in Si were found to trap transition metals strongly, suggesting application to impurity gettering in devices. Sci. Pure germanium is known to be a semiconductor and has an appearance that is the same as silicon. The mobility decreases many fold due to the influence of scattering by optical modes, By clicking accept or continuing to use the site, you agree to the terms outlined in our. Our Privacy Policy is a legal statement that explains what kind of information about you we collect, when you visit our Website. Seawater approximately 50 mS/cm. This is commonly measured across the opposite faces of a one-meter cube of material and described as an ohm meter (m). At theboiling pointthe two phases of a substance, liquid and vapor, have identical free energies and therefore are equally likely to exist. Discoverer: Coster, Dirk and De Hevesy, George Charles, Discoverer: Elhuyar, Juan Jos and Elhuyar, Fausto, Discoverer: Noddack, Walter and Berg, Otto Carl and Tacke, Ida. At temperatures near room temperature, the temperature dependence of the conductivity fo intrinsic germanium is found to equal: -E o =C (T 3/2' )exp 2kT where C is a temperature-independent constant and T is in Kelvins. m. Electrical resistivity and its converse, electrical conductivity, is a fundamental property of a material that quantifies how strongly it resists or conducts the flow of electric current. volume124, Articlenumber:381 (2018) The table above is based on 20 o C reference.. A 113(1), 207 (2014), J.Y.M. Learn more about Institutional subscriptions, C. Claeys, E. Simoen, Germanium-based Technologies from Materials to Devices, (Elsevier BV, Oxford, Amsterdam, 2007), B. Depuydt, A. Theuwis, I. Romandic, Mat. Up to date, curated data provided by Mathematica 's ElementData function from Wolfram Research, Inc. Proc. Hung, J.R. Gliessman, Phys. The electrical and thermal conductivities of metalsoriginate fromthe fact that theirouter electrons are delocalized. Google Scholar, E.E. The key variable in applying Ohm's Law is a metal's resistivity. In general,meltingis aphase changeof a substance from the solid to the liquid phase. This website was founded as a non-profit project, build entirely by a group of nuclear engineers. The vibrations of atoms are not independent of each other, but are rather strongly coupled with neighboring atoms. Conductivity is a measure of how well a material conducts an electric current. In a semiconductor, there are two types of charge carriers namely free electrons and holes. Using Equation above, calculate the intrinsic electrical conductivity of germanium at 140C. For example, in a sample of germanium at room temperature, the intrinsic carrier concentration is 2.5 x 1019 per m3. This changes the carrier concentration and transforms n-type germanium into p-type. if a donar impurity atoms are added to the extent to one part in ( 10) 6 germanium atoms at room temperature. Calculate conductivity of a germanium sample. The coolants used in nuclear reactors include water or liquid metals, such as sodium or lead. High Temperature Circular; Indirect Cooled Magnetron; Rotary Magnetron; UHV Sputtering; Request Circular Info; . Explain the difference of the conduction and valence bands of the different materials. A low resistivity indicates a material that readily allows the flow of electric current. Summary The idea of conduction by electrons in the energy bands of an impurity system is examined. At low temperature, no electron possesses sufficient energy to occupy the conduction band and thus no movement of charge . al. Thermal expansionis generally the tendency of matter to change its dimensions in response to a change in temperature. Draw the Bohr Model of Silicon, Germanium and Gallium Arsenide. Some example values: Distilled water 0,05 S/cm to 1 S/cm. Table 1 gives the value of and other important physical quantities for Ge and Si. Tax calculation will be finalised during checkout. On application of an electric field E, both electrons and holes drifts to contributes towards the drift current. (2- sentences) For the first time, planar high-purity germanium detectors with thin amorphous germanium contacts were successfully operated directly in liquid nitrogen and liquid argon in a cryostat at the Max-Planck-Institut fr Physics in Munich. . ADS If a single ball strikes multiple other balls, each of those will carry only a fraction of the energy. Armantrout, IEEE Trans. This shows that electrical conductivity of a semiconductor increases with the increase of temperature, i.e., a semiconductor has a negative temperature coefficient of resistance. Like the element silicon, germanium also reacts with oxygen to form complexes in nature. Discoverer: McMillan, Edwin M. and Abelson, Philip H. Discoverer: Glenn T. Seaborg, Joseph W. Kennedy, Edward M. McMillan, Arthur C. Wohl, Discoverer: Glenn T. Seaborg, Ralph A. James, Leon O. Morgan, Albert Ghiorso, Discoverer: Glenn T. Seaborg, Ralph A. James, Albert Ghiorso, Discoverer: Stanley G. Thompson, Glenn T. Seaborg, Kenneth Street, Jr., Albert Ghiorso, Discoverer: Stanley G. Thompson, Glenn T. Seaborg, Bernard G. Harvey, Gregory R. Choppin, Albert Ghiorso, Discoverer: Albert Ghiorso, Glenn T. Seaborg, Torbrn Sikkeland, John R. Walton, Discoverer: Albert Ghiorso, Torbjrn Sikkeland, Almon E. Larsh, Robert M. Latimer, Copyright 2023 Periodic Table | All Rights Reserved |. Haller, W.L. . K). Discoverer: Scientists at Dubna, Russia (1964)/Albert Ghiorso et. . 1, Issue 3, IEEE Transactions on Electron Devices, Vol. al. "Electrical Conductivity of Metals." of a-Ge is on the order of 2.13$$^{-0.05}_{+0.07}$$A to 5.07$$^{0.83}_{+2.58}$$A,depending on the density of states near the Fermi energy level within bandgap. Engineering Electrical Engineering Q1. Diamond electrical conductivity is approximately 0.001. For scattering of electrons by polar optical phonons, the conductivity is shown to depend essentially on the temperature . Magnetic susceptibility of Germanium is . If you continue to use this site we will assume that you are happy with it. Mercury. 10XX,52,11XX,17,12XX,7,13XX,4,15XX,16,3XXX,2,40XX,10,41XX,12,43XX,5,44XX,4,46XX,5,47XX,3,48XX,3,5XXX,23,6XXX,3,71XX,1,8XXX,22,92XX,5,93XX,1,94XX,4,98XX,2,AISI,66,ASTM,172,Atomic-Mass,327,Atomic-Number,436,Atomic-Radius,86,Atomic-Symbol,329,Atomic-Volume,94,Austenitic,56,Boiling-Point,94,bp1,97,CBS,6,Chemical-Elements,100,Chemical-Symbol,217,CMDS,13,Coefficient-of-Thermal-Expansion,85,Covalent-Radius,87,Crystal-Structure,109,CS,17,CVS,3,Density,297,Duplex,6,el1,100,Elastic-Modulus,30,Electrical-Conductivity,79,Electro-Affinity,87,Electron-Configuration,109,Electronegativity,102,Electrons-per-Shell,111,Enthalpy-of-Fusion,93,Enthalpy-of-Vaporization,95,Ferritic,12,fp1,38,fs1,45,Group-Number,218,HCS,14,Heat-of-Fusion,87,Heat-of-Vaporization,85,HMCS,16,Ionic-Radius,78,Ionization-Energy,102,Ionization-Potential,101,l1,438,LCS,21,List,281,lp1,69,Martensitic,6,MCS,17,MDS,14,Melting-Point,96,mm1,2,mp1,99,MS,4,NCMDBS,6,NCMDS,31,NCS,2,NMDS,8,Oxidation-States,104,p1,44,Period-Number,107,pr1,53,Properties,40,RCLS,1,RCS,16,ref1,5,RRCLS,3,RRCS,4,SAE,201,Site,2,SMS,5,Specific-Gravity,83,Specific-Heat,92,Specific-Weight,1,SS,80,Tests,2,Thermal-Conductivity,105,tm1,274,Valence-Electrons,98,wt1,26, Materials: Electrical Conductivity of Germanium (Ge) [& Color, Uses, Discovery 2022, Electrical Conductivity of Germanium (Ge) [& Color, Uses, Discovery 2022, https://1.bp.blogspot.com/-2TIKNCu3qMA/XV1OOmzQM0I/AAAAAAAAnZs/Fa_hUj_fBe4m6yLSM_ld8_MWsztTDf3OQCLcBGAs/s320/electrical-conductivity-of-germanium.webp, https://1.bp.blogspot.com/-2TIKNCu3qMA/XV1OOmzQM0I/AAAAAAAAnZs/Fa_hUj_fBe4m6yLSM_ld8_MWsztTDf3OQCLcBGAs/s72-c/electrical-conductivity-of-germanium.webp, https://materials.gelsonluz.com/2019/08/electrical-conductivity-of-germanium-ge.html, Not found any post match with your request, STEP 2: Click the link on your social network, Can not copy the codes / texts, please press [CTRL]+[C] (or CMD+C with Mac) to copy, How to calculate density when mass and volume are given, How a small number of atoms can be joined and form completely different substances. the device becomes a working conductivity-temperature-depth sensor capable of . 30, Issue 2. The intrinsic concentration ni varies with temperature as below: Where EGO is the forbidden energy gap at 00K in eV, k is the Boltmann consist in eV/deg K and A0 is a constant independent of temperature. and an insulator, such as glass. The electrical conductivity vs T of all samples is presented in Fig. Formula used: For intrinsic semiconductor, the electrical conductivity \[\sigma \] is given by \[\sigma =(ne{{\mu }_{e}}+pe{{\mu }_{h}})\] Where \[{{\mu }_{e}}\] and \[{{\mu }_{h}}\] denote the mobilities of electrons and holes respectively; n and p is the number of electrons and holes in the . (increasing temperature) decreases conductivity because the molecules . The temperature dependence of electrical conductivity of single-crystal and polycrystalline high-purity germanium (HPGe) samples has been investigated in the temperature range from 7 to 100 K. 16, Issue 3-4, IEEE Transactions on Nuclear Science, Vol. Terence Bell is a former writer who has been involved in the rare earth and minor metal industries for over 10 years. We use cookies to ensure that we give you the best experience on our website. Answer: Germanium is a semiconductor. The SI unit of electrical resistivity is the ohm-metre (m). Low-temperature anomalies in the Hall coefficient and electrical resistivity\char22{}a steep maximum and a change of the slope of the log resistivity versus $\frac{1}{T}$ curve in germanium, The energy levels of ordered impurities in semiconductors are formally equivalent to the energy levels of metallic hydrogen if a number of simplifying approximations are made. Mei, J. Govai et al., Appl. Appl. 302, 137 (1983). The heat transfer characteristics of a solid material are measured by a property called the thermal conductivity, k (or ), measured in W/m.K. Thermal expansionis generally the tendency of matter to change its dimensions in response to a change in temperature. Themelting pointof a substance is the temperature at which this phase change occurs. 2. Full Record; Other Related Research; Authors: Seitz, F Publication Date: Sun Nov 01 00:00:00 EDT 1942 Research Org. Semiconductors have conductivity in the intermediate range. Lattice defects produced by fast neutron bombardment introduce localized energy states into the forbidden band. Mobility also varies with applied electrical field. Liquids tend to have better thermal conductivity than gases, and the ability to flow makes a liquid suitable for removing excess heat from mechanical components. The mean free path also depends on the diameter of the molecule, with larger molecules more likely to experience collisions than small molecules, which is the average distance traveled by an energy carrier (a molecule) before experiencing a collision. *Note: The resistivity of semiconductors (metalloids) is heavily dependent on the presence of impurities in the material. 49, Issue 4, Journal of Applied Physics, Vol. and Gay-Lussac, L.-J. -05 ii: SAMPLE OHM-CM 3 5 3 1100 1000 900 800 -K FIG. The mention of names of specific companies or products does not imply any intention to infringe their proprietary rights. As temperature rises, intrinsic conductivity ni increases and the conductivity increases. Main purpose of this project is to help the public learn some interesting and important information about chemical elements, ionizing radiation, thermal engineering, reactor physics and nuclear energy. Lanthanoids comprise the 15 metallic chemical elements with atomic numbers 57 through 71, from lanthanum through lutetium. https://www.thoughtco.com/table-of-electrical-resistivity-conductivity-608499 (accessed March 4, 2023). She has taught science courses at the high school, college, and graduate levels. searching for physics beyond the Standard Model. Resistance . A 124, 381 (2018). Yang, G., Kooi, K., Wang, G. et al. J. Air and other gases are generally good insulators, in the absence of convection. Cavities were formed in Si and Ge by He ion implantation and annealing, and resultant chemical and electrical properties were investigated. Ok, so what is the electrical conductivity of an atom of Ge? E. Discoverer: De Marignac, Charles Galissard, Discoverer: De Marignac, Jean Charles Galissard, Discoverer: Ghring, Otto and Fajans, Kasimir. Equation (10) gives the conductivity of any semiconductor, whether intrinsic or extrinsic. Discoverer: Marinsky, Jacob A. and Coryell, Charles D. and Glendenin, Lawerence. At some point the amplitude of vibration becomes so large that the atoms start to invade the space of their nearest neighbors and disturb them and the melting process initiates. PubMedGoogle Scholar. In general, the thermal conductivity of gases increases with increasing temperature. It is a measure of a substance's ability to transfer heat through a material by conduction. The Cookies Statement is part of our Privacy Policy. 17, Issue 5, Journal of Applied Physics, Vol. Thequantaof the crystal vibrational field are referred to as phonons. A phonon is a collective excitation in a periodic, elastic arrangement of atoms or molecules in condensed matter, like solids and some liquids. ELECTRICAL PROPERTIES OF NEUTRON-IRRADIATED SILICON AT 76$sup 0$K: HALL EFFECT AND ELECTRICAL CONDUCTIVITY. Fornonmetallic solids,kis determined primarily bykph, which increases as the frequency of interactions between the atoms and the lattice decreases. Because the intermolecular spacing is much larger and the motion of the molecules is more random for the fluid state than for the solid state,thermal energy transportis less effective. Air and other gases are generally good insulators, in the absence of convection. Swierkowski, G.A. Pike, C.H. On a billiard table, this occurs when a ball strikes against another single ball, passing most of its energy onto the next ball. In physics, afluidis a substance that continually deforms (flows) under an applied shear stress. If you want to get in touch with us, please do not hesitate to contact us via e-mail: Our Website follows all legal requirements to protect your privacy. Discoverer: Corson, Dale R. and Mackenzie, K. R. The actinide or actinoid series encompasses the 15 metallic chemical elements with atomic numbers from 89 to 103, actinium through lawrencium. Tin is a metal with a high conductivity. As can be seen, theboiling pointof a liquid varies depending upon the surrounding environmental pressure. So, although they can conduct electricity, they are inefficient at the task. Table of Resistivity and Conductivity at 20C, Factors That Affect Electrical Conductivity. 1) You may use almost everything for non-commercial and educational use. 2023 Springer Nature Switzerland AG. The temperature dependence of electrical conductivity of single-crystal and polycrystalline high-purity germanium (HPGe) samples has been investigated in the temperature range from 7 to 100K. The conductivity versus inverse of temperature curves for three single-crystal samples consist of two distinct temperature ranges: a high-temperature range where the conductivity increases to a maximum with decreasing temperature, and a low-temperature range where the conductivity continues decreasing slowly with decreasing temperature. (0 K), the electrical conductivity of a semiconductor has a value of zero (i.e., the conductivity is at its minimum) whereas a metal exhibits its maximum electrical conductivity at absolute zero; furthermore, conductivity increases with increasing temperature in a . Sci. 1. The heat can be removed by channeling the liquid through a heat exchanger. The temperature dependence of electrical conductivity is simulated by curve-fitting the G (, T) function to experimental conductivity versus temperature data in terms of the parameter, E = E E F is the energy of the bottom of the conduction band and E F is the Fermi energy. The heat transfer characteristics of a solid material are measured by a property called the thermal conductivity, k (or ), measured in W/m.K. Meindl, IEEE Trans. The information contained in this website is for general information purposes only. In fact, in pure metals such as gold, silver, copper, and aluminum, the heat current associated with the flow of electrons by far exceeds a small contribution due to the flow of phonons. Lee, I.C. Resistivity is the reciprocal of conductivity and its temperature dependence is given by (4) Where Eg - band gap of the material T - Temperature in kelvin K - Boltzmann constant, K - 8.6x10-5 eV/K The resistivity of a semiconductor rises exponentially on decreasing the temperature. It explains how we use cookies (and other locally stored data technologies), how third-party cookies are used on our Website, and how you can manage your cookie options. ThoughtCo. 1) Note! However, in marine settings, EC often exceeds the range where two-pole sensors provide reliable results. At the melting point the two phases of a substance, liquid and vapor, have identical free energies and therefore are equally likely to exist. 36.28%. When considered as the temperature of the reverse change from liquid to solid, it is referred to as the freezing point or crystallization point. Electrical conductivity in metals is a result of the movement of electrically charged particles. Engineering Electrical Engineering 2. Similar definitions are associated with thermal conductivities in the y- and z-directions (ky, kz), but for an isotropic material the thermal conductivity is independent of the direction of transfer, kx = ky = kz = k. When electrons and phonons carry thermal energy leading to conduction heat transfer in a solid, the thermal conductivity may be expressed as: Metalsare solids and as such they possess crystalline structure where the ions (nuclei with their surrounding shells of core electrons) occupy translationally equivalent positions in the crystal lattice. The density of carriers in the doped semiconductor (10 16 cm-3) is much higher than in the undoped material (~10 10 cm-3), so the conductivity is also many orders of magnitude higher. Below the boiling point, the liquid is the more stable state of the two, whereas above the gaseous form is preferred. Thethermal conductivity of gasesis directly proportional to the density of the gas, the mean molecular speed, and especially to themean free pathof molecule. One siemens is equal to the reciprocal of one ohm. Find step-by-step Engineering solutions and your answer to the following textbook question: A metal alloy is known to have electrical conductivity and electron mobility values of $1.2 \times 10^{7}(\Omega \cdot \mathrm{m})^{-1}$ and $0.0050 \mathrm{m}^{2} / \mathrm{V} \cdot \mathrm{s}$, respectively. Phys. Themelting pointalso defines a condition in which the solid and liquid can exist in equilibrium. Growth 352, 43 (2012), G. Yang, J. Govani, H. Mei et al., Cryst. It is shown that , which lies in the band gap region . Accordingly, transport of thermal energy may be due to two effects: The unique feature of metals as far as their structure is concerned is the presence of charge carriers, specificallyelectrons. In metals the conductivity decreases with increasing temperature. Discoverer: Marinsky, Jacob A. and Coryell, Charles D. and Glendenin, Lawerence. At room temperature, it exhibits a low conductivity. 1) You may use almost everything for non-commercial and educational use. Technol. 76 Ge. In contrast, for alloys, the contribution of kph to k is no longer negligible. Semiconductor metals (or metalloids) have a higher number of valence electrons (usually four or more). Silicon and germanium are similar to each other and have an intermediate conductivity. Vn (Vp) is the velocity of electron (hole) is meters/sec. Because valence electrons are free to move, they can travel through the lattice that forms the physical structure of a metal. The transfer of energy is strongest when there is little resistance. However, in other classes of materials, known as semiconductors (e.g. Technol. Table of Electrical Resistivity and Conductivity. Facilities for such in-pile measurements of electrical conductivity, Hall coefficient, and thermoelectric power are described. The detectors were fabricated at the Lawrence Berkeley National Laboratory and the University of South Dakota, using crystals grown at the University of South Dakota. : National Defense Research Committee When you visit the site, Dotdash Meredith and its partners may store or retrieve information on your browser, mostly in the form of cookies. Electrical conductivity is a basic property of material. (2021, August 3). Solids are similar to liquids in that both are condensed states, with particles that are far closer together than those of a gas. At sufficiently high temperatures kph 1/T. In contrast, the conductivity versus inverse of temperature curves for three polycrystalline samples, in addition to a high- and a low-temperature range where a similar conductive behavior is shown, have a medium-temperature range where the conductivity decreases dramatically with decreasing temperature. Fluidsare a subset of the phases of matter and includeliquids,gases, plasmas and, to some extent, plastic solids. Thermal expansion is common for solids, liquids and for gases. From equations (15) and (16), we find that EG at room temperature is 0.72 (1.1) eV for Ge (Si). Therefore, many insulating materials (e.g.polystyrene) function simply by having a large number ofgas-filled pocketswhichprevent large-scale convection. Understanding Electrical, Thermal, and Sound Conductors, Superconductor Definition, Types, and Uses, The Basics: An Introduction to Electricity and Electronics, Rhodium, a Rare Platinum Group Metal, and Its Applications, Find the Anode and Cathode of a Galvanic Cell, Effect of Relative Humidity and Sea Level Pressure on Electrical Conductivity of Air over Indian Ocean, Ph.D., Biomedical Sciences, University of Tennessee at Knoxville, B.A., Physics and Mathematics, Hastings College. A slice of germanium conducts when heated. In the case of Germanium the electrical conductivity is 1.45e-8 10^6/cm ohm. Goulding, Adv. Their contribution to the thermal conductivity is referred to as theelectronic thermal conductivity, ke. The regularity of the lattice arrangement has an important effect onkph, with crystalline (well-ordered) materials likequartz having a higher thermal conductivity than amorphous materials like glass. Bell, Terence. 7.61%. The pressure at which vaporization (boiling) starts to occur for a given temperature is called thesaturation pressure. See also: Mechanical Properties ofGermanium. Correct option is D) As the temperature increases, the thermal motion of electrons also increases which results in increasing of the conductivity of the Ge crystal. If it is not isometric, there may be different expansion coefficients for different crystallographic directions, and the crystal will change shape as the temperature changes. 175, 23 (1986), G.E. The information contained in this website is for general information purposes only. Thelinear thermal expansion coefficientis defined as: whereLis a particular length measurement anddL/dTis the rate of change of that linear dimension per unit change in temperature. Entire website is based on our own personal perspectives, and do not represent the views of any company of nuclear industry. Any addition of thermal energy results in a phase transition. The measurement data permits determination of the band gap between the valence band and the conduction band in germanium. The information contained in this website is for general information purposes only. Price excludes VAT (USA) Gallium - Electrical Resistivity and Electrical Conductivity, Zinc - Electrical Resistivity and Electrical Conductivity, Copper - Electrical Resistivity and Electrical Conductivity, Zinc Electrical Resistivity and Electrical Conductivity, Arsenic Electrical Resistivity and Electrical Conductivity. In fact, for crystalline, nonmetallic solids such as diamond, kphcan be quite large, exceeding values of k associated with good conductors, such as aluminum. Semantic Scholar is a free, AI-powered research tool for scientific literature, based at the Allen Institute for AI. Seager, J. Appl. Covalent bonds often result in the formation of small collections of better-connected atoms called molecules, which in solids and liquids are bound to other molecules by forces that are often much weaker than the covalent bonds that hold the molecules internally together. This is a preview of subscription content, access via your institution. Draw the Covalent Bonding of the semiconductor materials. Thus, at room temperature in Ge (Si), one atom out of about 10 9 (10 12) contributes one electron-hole pair through breaking of covalent bond.. Anyone you share the following link with will be able to read this content: Sorry, a shareable link is not currently available for this article. The inner layers of non-valence electrons "screen off" all of the nuclear charge except for t. Determine the conductivity and resistivity of pure germanium at `300K` assuming that at this temperature the concentration of germanium is `2.5xx10^(1. asked Dec 25, 2021 in Physics by Satishkumar (24.2k points . Question: At temperatures near room temperature, the temperature dependence of the conductivity for intrinsic germanium is found to equal Eg o = CT-3/2 exp p 2kT where Cis a temperature-independent constant and I is in Kelvins. Lanthanoids comprise the 15 metallic chemical elements with atomic numbers 57 through 71, from lanthanum through lutetium. In general: Most materials are very nearly homogeneous, therefore we can usually writek = k (T). The dashed line has been computed from equation (1). Solids 16, 207 (1960), H. Fritzsche, Phys. Due to its low conductivity, it is deemed unsuitable for use in electronic devices. The thermal conductivity of most liquids and solids varies with temperature. Under an electric field, free electrons move through the metal much like billiard balls knocking against each other, passing an electric charge as they move.