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electrical conductivity of germanium with temperature

Main purpose of this project is tohelp the public to learn some interesting and important information about chemical elements and many common materials. In general, substances expand or contract when their temperature changes, with expansion or contraction occurring in all directions. Electrical Conductivity of Metals - ThoughtCo Fe segregation as a tool to enhance electrical conductivity of grain Electrical resistivity, represented by the Greek letter (rho), is a measure of how strongly a material opposes the flow of electric current. The electrical and thermal conductivities of metalsoriginate fromthe fact that theirouter electrons are delocalized. 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. Rev. 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. It is these "free electrons" that allow metals to conduct an electric current. RI*HUPDQLXP OPTICAL INVESTIGATIONS OF - Institute of Physics ThoughtCo, Aug. 3, 2021, thoughtco.com/electrical-conductivity-in-metals-2340117. I'm Gelson Luz, mechanical engineer, welding specialist and passionate about: I am building this blog to be the best learning blog about engineering! Electrical properties of Germanium (Ge) - Ioffe Institute Rev. The conductivity of an intrinsic semiconductor depends on the surrounding temperature. 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. For n-type silicon: Relation Between Line Voltage and Phase Voltage in Delta Connection, Relation Between Line Voltage and Phase Voltage in Star Connection, Charge Densities in Extrinsic Semiconductor, Kirchhoffs Voltage Law Examples with Solution, Kirchhoff's Voltage Law Examples with Solution, Superposition Theorem Example with Solution, Induced EMF | Statically and Dynamically Induced EMF, Reciprocity Theorem Example with Solution, Transient Response in Series RC circuit having D.C. Excitation (First Order circuit). al. https://www.thoughtco.com/table-of-electrical-resistivity-conductivity-608499 (accessed March 4, 2023). However, in marine settings, EC often exceeds the range where two-pole sensors provide reliable results. In physics, afluidis a substance that continually deforms (flows) under an applied shear stress. Our Website follows all legal requirements to protect your privacy. Themelting pointalso defines a condition in which the solid and liquid can exist in equilibrium. In fact, lattice thermal conduction is the dominant thermal conduction mechanism in nonmetals, if not the only one. A. I B. III C. IV D. V. 3. Pike, C.H. Mobility and are expressed in meter2/volt-second. Semantic Scholar extracted view of "The low temperature electrical conductivity of n-type germanium" by S. Koenig et al. Air and other gases are generally good insulators, in the absence of convection. The intrinsic semiconductor has a very small conductivity. 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. 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. Semiconductors at room temperature (300 K) have electrical conductivity in the range of 10-7 to 104 S/meter. The information contained in this website is for general information purposes only. Google Scholar, C.S. On the other hand, ice (solid H2O) is a molecular compound whose molecules are held together by hydrogen bonds, which is effectively a strong example of an interaction between two permanent dipoles. In this article we will discuss different electrical properties of germanium and silicon like conductivity, drift current, concentration forbidden energy gap and mobility. Discoverer: Priestley, Joseph and Scheele, Carl Wilhelm, Discoverer: Ramsay, William and Travers, Morris, Discoverer: Ramsay, Sir William and Strutt, John (Lord Rayleigh), Discoverer: Del Rio, Andrs Manuel (1801) and Sefstrm, Nils Gabriel (1830), Discoverer: Lecoq de Boisbaudran, Paul-mile, Discoverer: Ramsay, Sir William and Travers, Morris, Discoverer: Bunsen, Robert Wilhelm and Kirchhoff, Gustav Robert, Discoverer: Perrier, Carlo and Segr, Emilio, Discoverer: Reich, Ferdinand and Richter, Hieronymus, Discoverer: Mller von Reichenstein, Franz Joseph, Discoverer: Ramsay, William and Travers, Morris William, Discoverer: Kirchhoff, Gustav and Bunsen, Robert. Their contribution to the thermal conductivity is referred to as theelectronic thermal conductivity, ke. 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. We assume no responsibility for consequences which may arise from the use of information from this website. On combining equations (2) and (6) we get, Where is the mobility of holes (electron) and equals. (2- sentences) Electrical conductivity and its converse, electrical resistivity, is a fundamental property of a material that quantifies how Germanium conducts the flow of electric current. Conduction in metals must follow Ohm's Law, which states that the current is directly proportional to the electric field applied to the metal. Seager, J. Appl. https://www.thoughtco.com/electrical-conductivity-in-metals-2340117 (accessed March 4, 2023). Phys. Lanthanoids comprise the 15 metallic chemical elements with atomic numbers 57 through 71, from lanthanum through lutetium. 352, Issue 1, Crystal Research and Technology, Vol. (auth). Demonstration. Note that Fourier's law applies for all matter . Adding a heat will convert the solid into a liquid with no temperature change. Cookies collect information about your preferences and your devices and are used to make the site work as you expect it to, to understand how you interact with the site, and to show advertisements that are targeted to your interests. Calculate its charge carrier density 'n e 'and electron mobility at room temperature. 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. The Electrical Conductivity of Silicon and Germanium Total electronic thermal conductivity in n-type germanium as a function of temperature. Note that Fouriers law applies for all matter, regardless of its state (solid, liquid, or gas), therefore, it is also defined for liquids and gases. In Figure 2 U is plotted against T, using the same results as are used in The law, named afterGerman physicist Georg Ohm, appeared in 1827 in a published paper laying out how current and voltage are measured via electrical circuits. Metalsin general havehigh electrical conductivity,high thermal conductivity, and high density. The electrical conductivity of pure germanium can be increased by. Table 1 gives the value of and other important physical quantities for Ge and Si. The atoms of metal elements are characterized by the presence of valence electrons, which are electrons in the outer shell of an atom that are free to move about. Vickers Hardness: converted from Mohs scale. 49, Issue 4, Journal of Applied Physics, Vol. That means a pure crystal of it has a valence band (full of electrons) that is only a little lower in energy from its conduction band (empty orbitals with lots of room for electrons). Thus by substituting the values we will get the electrical conductivity of germanium. Most recent implementations of low-cost electrical conductivity (EC) sensors intended for water quality measurements are based on simple two-pole designs. 1. 505, 3414 (1979), J. Martinez, J. Piqueras, Solid State Electron. the device becomes a working conductivity-temperature-depth sensor capable of . The coolants used in nuclear reactors include water or liquid metals, such as sodium or lead. 101/1-B, Chemical and electrical properties of cavities in silicon and germanium. Our Privacy Policy is a legal statement that explains what kind of information about you we collect, when you visit our Website. The activation energy for conduction is only 40-50 meV, so the conductivity does not change much with temperature (unlike in the intrinsic semiconductor) It is a measure of a substances ability to transfer heat through a material by conduction. a) Calculate the intrinsic electrical conductivity of germanium at 150C. Seawater approximately 50 mS/cm. Hubbard, F.S. 2 d. At room temperature, electrical conductivity () increases from 240 to 348 S cm 1 as the grain size decreases from 5 m to 0.26 m. Therefore, it is derived that more GBs in TiCo 0.7 Fe 0.3 Sb lead to an increase of the bulk electrical conductivity. Different materials have different bonding forces and therefore different expansion coefficients. At the melting point the two phases of a substance, liquid and vapor, have identical free energies and therefore are equally likely to exist. . (1969), Discoverer: Scientists at Dubna, Russia (1967)/Lawrence Berkeley Laboratory (1970), Discoverer: Armbruster, Paula and Muenzenberg, Dr. Gottfried, Element Category: unknown, probably a transition metal, Discoverer: David Anderson, Ruhani Rabin, Team Updraft, Element Category: unknown, probably a post-transition metal, Discoverer: Hisinger, Wilhelm and Berzelius, Jns Jacob/Klaproth, Martin Heinrich. Calculate conductivity of a germanium sample - Ques10 Pure Metals generally have. Correspondence to 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. Helmenstine, Anne Marie, Ph.D. (2020, August 27). Resistivity by Four Probe Method - Amrita Vishwa Vidyapeetham Electrical conductivity is the reciprocal quantity of resistivity. In an N-type semiconductor, the concentration of electron is 2 10 22 m -3. This article provides an overview. This table presents theelectrical resistivity and electrical conductivity of several materials. Thereafter Iogm increases very rapidly along a straight line which is the same for all specimens. Anderson, N. Apsley, Semicond. The table above is based on 20 o C reference.. In a pure semiconductor, n = p = ni. "Electrical Conductivity of Metals." Answer (1 of 2): Both silicon and germanium have four valence electrons. In contrast, for alloys, the contribution of kphto k is no longer negligible. Also as the conductivity of extrinsic semiconductor is more than that of intrinsic semiconductor, thus the conductivity of pure germanium increases by doping Ge crystal either with . A slice of germanium conducts when heated. The results are in agreement with those of other workers obtained with germanium of higher conductivity and using a slightly different calculation approach. Silicon and germanium are similar to each other and have an intermediate conductivity. Table of Electrical Resistivity and Conductivity. Thus, at room temperature in Ge (Si), one atom out of about 109 (1012) contributes one electron-hole pair through breaking of covalent bond. 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. Notes on the Electrical Conductivity of particular elements: Carbon: Value given for graphite. In gases, the thermal conduction is caused by diffusion of molecules from higher energy level to the lower level. In the experiment P7.2.1.5, the electrical conductivity of undoped germanium is measured as a function of the temperature to provide a comparison. Abstract. https://doi.org/10.1007/s00339-018-1803-2, DOI: https://doi.org/10.1007/s00339-018-1803-2. Up to date, curated data provided by Mathematica 's ElementData function from Wolfram Research, Inc. Tax calculation will be finalised during checkout. The melting point of ice is 0 C. "Electrical Conductivity of Metals." E. Discoverer: De Marignac, Charles Galissard, Discoverer: De Marignac, Jean Charles Galissard, Discoverer: Ghring, Otto and Fajans, Kasimir. These elements, along with the chemically similar elements scandium and yttrium, are often collectively known as the rare earth elements. The temperature dependent hopping distance and hopping energy are obtained for a-Ge fabricated as the electrical contact materials for high-purity Ge planar detectors. The heat transfer characteristics of a solid material are measured by a property called the thermal conductivity, k (or ), measured in W/m.K. 23, 297 (1980), D.A. E. Discoverer: De Marignac, Charles Galissard, Discoverer: De Marignac, Jean Charles Galissard, Discoverer: Ghring, Otto and Fajans, Kasimir. 35 refs. . 1) You may use almost everything for non-commercial and educational use. Light gases, such ashydrogenandheliumtypically havehigh thermal conductivity. Electrical conductivity in metals is a result of the movement of electrically charged particles. Substances in which electricity can flow are called conductors. Transport of thermal energy in solids may be generally due to two effects: Copyright 2023 Periodic Table | All Rights Reserved |, Zinc Boiling Melting Point Thermal Conductivity Expansion, Arsenic Boiling Melting Point Thermal Conductivity Expansion. This is a preview of subscription content, access via your institution. ENGINEERING PHYSICS -SEMICONDUCTING MATERIALS PROBLEMS KEYS. The SI unit of electrical resistivity is the ohm-metre (m). A current of 40 A is passed through a specimen of this alloy that is 35 mm thick. This work was supported by DOE DE-FG02-10ER46709, NSF OISE-1743790, NSF OIA-1738632 and the state of South Dakota. Using the electron and hole mobilities for silicon in Table $18.3,$ compute the electron concentration. Tin is a metal with a high conductivity. Conductors are the elements that have a very high conductivity range of the order 10 4 to 10 6 S/cm. conductivity were taken from a graph[1][7]. In general, the thermal conductivity of gases increases with increasing temperature. One siemens is equal to the reciprocal of one ohm. Electrical conductivity of high-purity germanium crystals at low 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. This in turn enables one to perform continuous simultaneous measurements of various parameters of germanium in the intrinsic region as functions of carrier concentration. 23, Issue 1, Journal of Physics and Chemistry of Solids, Vol. But volume charge density equals the number of electrons (holes) per unit volume multiplied by the charge of each carrier. Phys. The internal consistency of the parameters in the carriers (electrons, normal holes, and light holes) is also shown. Zirconium. Mobility The mobility of a charge varies as T-m over temperature range of 100 to 400 K. For Ge, m = 1.66 (2.33) for electron (hole), For Si, m = 2.5 (2.7) for electron (hole). The conductivity's dependences on the temperature and on the parameters of the quantum well are studied in the case of electron-phonon scattering. 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. Why are semiconductors valuable in modern . The volumetric thermal expansion coefficient is the most basic thermal expansion coefficient, and the most relevant for fluids. The standard units of conductivity is Siemens per meter. Lattice defects produced by fast neutron bombardment introduce localized energy states into the forbidden band. At theboiling pointthe two phases of a substance, liquid and vapor, have identical free energies and therefore are equally likely to exist. The atoms in a solid are tightly bound to each other, either in a regular geometric lattice (crystalline solids, which include metals and ordinary ice) or irregularly (an amorphous solid such as common window glass), and are typically low in energy. Growth 352, 43 (2012), G. Yang, J. Govani, H. Mei et al., Cryst. Electrical conductivity of high-purity germanium crystals at low Both of these bands are formed by the overlap of atomic orbitals Across the. Silicon is less sensitive to change in temperature than Germanium. >> Semiconductor Electronics: Materials, Devices and Simple Circuits. Electric conductivity may be represented by the Greek letter (sigma), (kappa), or (gamma). Draw the Bohr Model of Silicon, Germanium and Gallium Arsenide. By the same token, the most effective conductors of electricity are metals that have a single valence electron that is free to move and causes a strong repelling reaction in other electrons. In particular, diamond has the highest hardness and thermal conductivity (k = 1000 W/m.K) of any bulk material. Terence Bell is a former writer who has been involved in the rare earth and minor metal industries for over 10 years. Applied Physics A Why does the resistance of germanium decrease with a rise in - Quora The Cookies Statement is part of our Privacy Policy. PDF Chap 19 Solns - Simon Foucher At low temperature, no electron possesses sufficient energy to occupy the conduction band and thus no movement of charge . Whereas in the case of conductors, when the temperature increases its resistivity increases as electrons collide more frequently with vibrating atoms. 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 key variable in applying Ohm's Law is a metal's resistivity. 53, Issue 1, Microelectronics Journal, Vol. Step 1: Classification of elements. Due to this property one material can conduct electricity. On applying an electric field of intensity 10 V/cm across a semiconductor at a certain temperature the average drift velocity of free electrons is measured to be 70 m/s. 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. Extrinsic Semiconductors - Engineering LibreTexts Entire website is based on our own personal perspectives, and do not represent the views of any company of nuclear industry. Themelting pointis the temperature at which the disruptive vibrations of the particles of the solid overcome the attractive forces operating within the solid. 23, Issue 4, Semiconductor Science and Technology, Vol. Germanium - Electrical Resistivity and Electrical Conductivity Semiconductor Question and Answer with explanation - Electrical Exams Helmenstine, Anne Marie, Ph.D. "Table of Electrical Resistivity and Conductivity." 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. Summary The idea of conduction by electrons in the energy bands of an impurity system is examined. PubMedGoogle Scholar. On the other hand, water boils at 350C (662F) at 16.5 MPa (typical pressure of PWRs). Thethermal conductivityof gases and liquids is therefore generally smaller than that of solids. Equation (10) gives the conductivity of any semiconductor, whether intrinsic or extrinsic. At room temperature, it exhibits a low conductivity. For these materials, the area and volumetric thermal expansion coefficient are, respectively, approximately twice and three times larger than the linear thermal expansion coefficient (V= 3L). In general: Most materials are very nearly homogeneous, therefore we can usually write k = k (T). The Cookies Statement is part of our Privacy Policy. Cells, 1.5 V, with holders, 3 Lamp in holder, 6 V 3 W approx Mounted slice of germanium, see technical note The liquid can be said to be saturated with thermal energy. At room temperature (300 K), for Ge (Si) per cm3. ThoughtCo. 1) You may use almost everything for non-commercial and educational use. it passes through a minimum. Extrinsic Semiconductors - Definition, Types and Properties | BYJU'S 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 . Each has a single valence electron that moves with little resistance and causes a strong repelling reaction. The dissociation energies for Si-H and Ge-H surface monohydride bonds were determined, showing that H chemisorption on Si is energetically stable with respect H{sub 2} gas whereas H chemisorption on Ge is not. In general: Most materials are very nearly homogeneous, therefore we can usually writek = k (T). Cheng, Electrical properties of lightly doped polycrystalline silicon., J. Appl. This is the case in the most conductive metals, such as silver, gold, and copper. 2) You may not distribute or commercially exploit the content, especially on another website. Alternation of gas pocket and solid material causes that the heat must be transferred through many interfaces causing rapid decrease in heat transfer coefficient. The Cookies Statement is part of our Privacy Policy. 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. A liquid at high pressure has a higher boiling point than when that liquid is at atmospheric pressure. Hung, J.R. Gliessman, Phys. Class 12. 10.5: Semiconductors- Band Gaps, Colors, Conductivity and Doping 4. 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. Both the boiling points of rhenium and tungsten exceed 5000 K at standard pressure. Swierkowski, G.A. Pure germanium is known to be a semiconductor and has an appearance that is the same as silicon. 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. Department of Physics, The University of South Dakota, Vermillion, SD, 57069, USA, Gang Yang,Kyler Kooi,Guojian Wang,Hao Mei,Yangyang Li&Dongming Mei, You can also search for this author in Journal of Physics and Chemistry of Solids, Abstract Studies were made of electrical conductivity at low temperatures in germanium crystals grown with indium and antimony EE majority and minority impurities respectively. Its electrical conductivity is 112 -1 m -1. Therefore, many insulating materials (e.g.polystyrene) function simply by having a large number ofgas-filled pocketswhichprevent large-scale convection. Note that, electrical resistivity is not the same as electrical resistance. The lower the resistivity, the more readily the material permits the flow of electric charge. Electrical Conductance Conductivity of Metal Semiconductor and Cite this article. per cm 3. 8. In p-type semiconductor, np << Pp, Further . Solved Problems: Semiconducting Materials - BrainKart The heat can be removed by channeling the liquid through a heat exchanger. In which column on the periodic table do the elemental semiconductors reside? Electrical conductivity or specific conductance is the reciprocal of electrical resistivity. Report No. Hence for n-type semiconductor. At room temperature, because of thermal energy, some of elctron hole pairs are generated. A metal alloy is known to have electrical conductivity and e | Quizlet Solids 16, 207 (1960), H. Fritzsche, Phys. Assume that only one electron of each atom takes part in conduction process. They are mainly classified into two types as follows: Intrinsic semiconductors. The heat transfer characteristics of a solid material are measured by a property called the thermal conductivity, k (or ), measured in W/m.K. Cavity walls in Si were found to trap transition metals strongly, suggesting application to impurity gettering in devices.

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electrical conductivity of germanium with temperature

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electrical conductivity of germanium with temperature