The phenomenon of piezoresistivity dates back to 1954 when smith et al. Two dimensional 2d semiconductors have attracted attention for a range of electronic applications, such as transparent, flexible field effect transistors and sensors owing to their good optical transparency and mechanical flexibility. Piezoresistance in silicon and its nanostructures author arxiv. The effect of stress on doped silicon and germanium has been known since the work of smith at bell laboratories in 1954. Efforts to exploit 2d semiconductors in electronics are hampered, however, by the lack of efficient methods for their synthesis at levels of quality. He found that both ptype and ntype silicon and germanium exhibited much greater piezoresistive effect than metals. The transverse component of the electrical conductivity tensor. The effect of piezoresistance is similar to the strain gauge effect in a metal material, but the differences between them are quite. Piezoresistance of nanoscale silicon up to 2gpa in. Mar 01, 2009 read piezoresistance effect of strained and unstrained fullydepleted silicon oninsulator mosfets integrating a hfo 2 tin gate stack, solidstate electronics on deepdyve, the largest online rental service for scholarly research with thousands of academic publications available at your fingertips. Its origin in bulk, crystalline materials like silicon, is principally a change in the electronic structure which leads to a modification of the charge carriers effective mass. Temperature dependence of the piezoresistance effects of p.
Piezoresistors are connected in wheatrstones bridge format to reduce temperature effects a bit. The study of the effect of the temperature and doping level on characteristics of these sensors is essential to define the parameters that cause the output characteristics drift. The resistors are created by etching the poly silicon germanium. Piezoresistive effect in silicon and germanium was discovered by charles smith in 1954. Request pdf piezoresistance in strained silicon and strained silicon germanium. Recently, the knowl edge of the piezoresistance effect has been required not only. Over the last years, the microelectronic industry is increasingly considering the use of organic semiconductors. Piezoresistance effect article about piezoresistance effect. Piezoresistance is the change in the electrical resistance, or more specifically the resistivity, of a solid induced by an applied mechanical stress. Smith l discovered the piezoresistance effect of semiconductors having anisotropic energy band structures, such as silicon and germanium, they have been widely used as stress and strain sensors. The complete tensor piezoresistance has been determined. Giant piezoresistance effect in silicon nanowires nature.
The piezoresistance effect of silicon1 has been widely used in mechanical sensors2,3,4, and is now being actively explored in order to improve the performance of silicon transistors5,6. The origin of the shear piezoresistance coefficient. Smithpiezoresistance effect in germanium and silicon. Principles of a varied group of new semiconducting, piezoresistive stress and strain transducers are outlined. Lynn fuller piezoresistance page 3 rochester institute of technology microelectronic engineering charles smith 1954. A four point bending setup is proposed and designed to analyze the piezoresistance effect. Anomalous piezoresistance effect in ultrastrained silicon. In this paper we demonstrate that under ultrahigh strain conditions ptype single crystal silicon nanowires possess an anomalous piezoresistance effect.
Piezoresistance definition of piezoresistance by the. The reduced dimensions and increased surfacetovolume ratio should further contribute to the enhancement. Hence, semiconductor strain gauges with a very high coefficient of sensitivity can be built. This effect had been investigated and widely used for sensing. This is followed by a discussion on the piezoresistance coefficients, their need, and relevance to understanding strainenhanced electron and hole mobility. The origin of this effect in bulk, crystalline materials like silicon, is principally a change in the electronic structure which leads to a modification of the charge carriers effective mass. Longitudinal piezoresistance and conductance of the ptype. The silicon piezoresistance effect has been widely used for about half a century in various sensor products and applications.
A graphical representation of the pr on crystallographic orientations and the effect of. Effect of temperature and doping on the piezoresistity the basic conclusion of kandas work 7 is that the piezoresistance coefficient obeys to the following relation. Optimization of design parameters for bulk micromachined. As pressure is applied, the diaphragm deforms and the resulting strain impacts the carrier mobility and number density. The special setup enables the application of pure uniaxial tensile strain along the 111. Bir, effect of deformation on the energy spectrum and the electrical properties of imperfect germanium and silicon, sov. Silicon has a relatively large piezoresistance effect which has been known since 1954.
The complete tensor piezoresistance has been determined experimentally for these materials and expressed in terms of the pressure coefficient of resistivity and two simple shear coefficients. Yamada, nonlinearity of the piezoresistance effect of ptype silicon diffused layers, ieee trans. With resistivity change under mechanical stress due to deformation of the silicon crystal structure, the piezoresistive coefficient is used to define the relative change in resistance per unit stress by. Piezoresistance effect an overview sciencedirect topics.
Nk 0,300 stands for piezocoeficient valuefor the low doped silicon, n is a doping level. One group of devices consists of gauges in the form of a thin rectangular sheet which is bonded to the test piece, and whose resistance change can be expressed as a simple function. Definition of piezoresistance coefficients since c. The piezoresistance effect in ntype strained silicon has been well explained by the manyvalley model 21, while, in ptype strained silicon, the piezoresistance effect has not yet been fully understood and characterized. Piezoresistivity, silicon, four point bending i introduction silicon piezoresistive sensors are among the earliest micromachined devices and are still commonly used in the commercial field today. The piezoresistive effect describes the change in electrical resistance that occurs when an external force is applied to a semiconductor. The proposed double polysilicon germanium nanowire pressure sensor gave a sensitivity of.
Murakami, structural effect of ic plastic package on residual stress in silicon chips, proc. The effect of piezoresistance in germanium and silicon was discovered by c. Many types of accelerometers also make use of the piezoresistive effect. Investigation of piezoresistive effect in ptype silicon. The effect of doping concentration on temperature sensitivity is also investigated. The principle of the piezoresistance effect pr of n and psi is explained by the carriertransfer mechanism and the effective mass change. A computational approach for simulating ptype silicon.
Piezoresistance pzr is the change in the electrical resistivity of a solid induced by an applied mechanical stress. Jun 11, 2004 principles of a varied group of new semiconducting, piezoresistive stress and strain transducers are outlined. Since then, the piezoresistivity of inorganic semiconductors has been extensively studied. The first order piezoresistance coefficients are examined in the ntype silicon structures with different dimensionality of electron gas. Piezoresistivity of silicon quantum well wire iopscience. Johns mechanical engineering department brigham young university provo,utah 84602 abstract the piezoresistive effect of silicon is often utilized in sensors. The piezoresistive effect in silicon and germanium was first discovered in 1954 by smith 3. In boron doped poly silicon germanium films, the decreased resistance with increasing germanium fraction is due both to the. The piezoresistive effect of semiconductor materials can be several orders of magnitudes larger than the geometrical effect and is present in materials like germanium, polycrystalline silicon, amorphous silicon, silicon carbide, and single crystal silicon.
Piezoresistive effect in semiconductors silicon and. The detail research involves quantum kinetic approach to calculation of the kinetic coefficients conductivity, mobility, concentration of electrons in the strained and unstrained states. Beddiaf abdelaziz, kerrour fouad2, salah kemouche2. Characteristic and analysis of silicon germanium material as mems pressure sensor. S smith smi53 first discovered the piezoresistance effect of semiconductors having anisotropic band structures such as silicon 50 years ago, the semiconductors have found applications in pressure and mechanical stress sensors kan91. Unlike the piezoelectric effect, it cannot be used to generate a voltage across the device. An investigation was made of the longitudinal and transverse piezoresistance and electrical conductivity of ptype silicon under conditions of uniaxial compression, x. The design is targeted for measurement of pressure up to 200 bar for nuclear reactor applications. Hidden orbital polarization in diamond, silicon, germanium. Due to the crystalline nature of silicon, the sensitivity of the piezoresistive effect depends on many things including the. The piezoresistive effect is a change in the electrical resistivity of a semiconductor or metal.
Piezoresistive pressure sensors based on silicon have a large thermal drift because of their high sensitivity to temperature. Oct 31, 2014 in a piezoresistive pressure sensor, a piezoresistor is usually implanted in the surface of a thin silicon diaphragm. Piezoresistivity of silicon arises from the deformation of the energy bands as a result of applied. Piezoresistive effect in semiconductors silicon and germanium. Fahy2 1tyndall national institute, university college cork, lee maltings, dyke parade, cork, ireland 2tyndall national institute and department of physics, university college cork, ireland received 26 march 2012. A graphical representation of the pr on crystallographic orientations and the effect of impurity concentration on the pr are given for n. Smith c s 1954 piezoresistance effect in germanium and silicon phys. Piezoresistance of nanoscale silicon up to 2gpa in tension. Chapter 2 strained silicon modeling and piezoresistance introduction the first section of this chapter introduces the relation between the piezoresistive effect and strained silicon mosfet. Abstract uniaxial tension causes a change of resistivity in silicon and germanium of both n and p types. The change of electric resistance in silicon piezoresistance gauge can thus be expressed as 16 r.
Piezoresistive effect definition comsol multiphysics. A four point bending setup is proposed and designed to analyze the piezoresistance effect in ptype silicon. Piezoresistance effect article about piezoresistance. These devices have in common the utilization of the transverse or shear piezoresistive effect. Its origin in bulk crystalline materials like silicon is principally a change in the electronic structure which leads to a modification of the effective mass of charge carriers. Semiconducting stress transducers utilizing the transverse.
Since then, researchers have extensively reported on microscale, piezoresistive strain gauges, pressure sensors, accelerometers, and cantilever forcedisplacement sensors, including many commercially successful devices. Finite element analysis study has been carried out to optimize the design parameters for bulk micromachined silicon membranes for piezoresistive pressure sensing applications. Electrical piezoresistive effect what is the piezoresistive effect. The piezojunction effect in silicon sensors and circuits. Characteristic and analysis of silicon germanium material. In a typical silicon pressure sensor made on 001 silicon wafer, membrane will be formed by anisotropic etching in koh an etch stops on 111. Us3049685a us29837a us2983760a us3049685a us 3049685 a us3049685 a us 3049685a us 29837 a us29837 a us 29837a us 2983760 a us2983760 a us 2983760a us 3049685 a us3049685 a us 3049685a authority us united states prior art keywords gauge zone zones body strain prior art date 19600518 legal status the legal status is an assumption and is not a legal conclusion. It was found that the resistance of a germanium or silicon filament changed when the material was stressed. Giant piezoresistance of ptype nanothick silicon induced. Energy spectrum of holes for the low dimensional structures was accepted in the quasiclassical approximation. Giant piezoresistance of ptype nanothick silicon induced by. Remarkably, we can now understand, from the same principles, why the hidden spin polarization in diamond, silicon or germanium is very small and why that in mos 2 or wse 2 is very large.
Nonlinear piezoresistance in ptype silicon springerlink. Quantum confinement effects in transferrable silicon. May 08, 2012 longitudinal piezoresistance coefficient. Piezoresistance in silicon and its nanostructures journal. Characteristic and analysis of silicon germanium material as. Read piezoresistance effect of strained and unstrained fullydepleted silicononinsulator mosfets integrating a hfo 2 tin gate stack, solidstate electronics on deepdyve, the largest online rental service for scholarly research with thousands of academic publications available at your fingertips. Piezoresistance definition of piezoresistance by the free. Introduction piezoresistance in silicon and germanium was discovered by smith in 1954. Remarkable piezoresistance effect on the flexible strain.
In this study, we adopted the model of kanda to determine the effect of the temperature and. Hansen1,2 1department of micro and nanotechnology, dtu nanotech building 345 east, technical university of. Piezoresistance in silicon and its nanostructures journal of. Silicon piezoresistive stress sensors and their application. The 1, piezoresistance effect is defined as the changes of electric resistance in a material with strain under pressure, such as silicon, organic semiconductor, and piezoresistance composite, 4. The mechanical behavior of bulk micromachined silicon membranes in terms of deflection and stress generation has. One group of devices consists of gauges in the form of a thin rectangular sheet which is bonded to the test piece, and whose resistance change can be expressed as a simple function of the. The piezoresistance effect is defined as change in resistance due to applied stress. In smart silicon hall sensors with mechanical stress compensation the piezoresistance effect leads to a sigma.
1155 1289 27 327 63 215 645 1014 192 827 1383 122 325 1607 829 289 100 767 1131 66 787 25 847 448 1241 786 1298 364 130 37 227 819 75 644 1282 888 146 1589 182 1385 1299 263 1168 503 122 512 4 462 602 1132 226