DE1590387C

DE1590387C - Transducer

Info

Publication number: DE1590387C
Application number: DE19661590387
Authority: DE
Inventors: Henry Lewis Ann Arbor Mich Stadler (V St A )
Original assignee: Ford Motor Co
Current assignee: Ford Motor Co
Priority date: 1965-03-05
Filing date: 1966-02-28
Publication date: 1973-08-02

Description

In einem praktischen Ausführungsfall wurde für einen elektrisch polarisierbaren Grundkörper aus Barium-Titanat festgestellt, daß er bei einer Dicke von 0,005 cm seine Polarisation innerhalb einer Sekunde bei Raumtemperatur umkehrt, wenn eine Spannung von etwa 1 bis 2 Volt angelegt wird. Bei einer Dicke von 0,05 cm wurde dazu eine Spannung von etwa 10 Volt benötigt. Auf denselben Grundkörper wurden Goldschichten mit Schichtdicken zwischen 100 und 1300 Angström aufgedampft und die Änderung der Widerstandswerte gemessen. Dabei zeigte sich, daß die Änderung der Widerstandswerte, die sowohl bei einer völligen wie auch bei einer nur teilweisen Umkehrung der Polarisation des Barium-Titanats erhalten wurden, proportional zu der von diesem gelieferten Oberflächenladung erfolgte, wobei die dünneren Goldschichten die größeren Widerstandsänderungen erfuhren. Für die Verhältnisse einer völligen Umkehrung der Polarisation wurden Widerstandswerte zwischen 25 Ohm für eine Goldschicht von 100 Angström und 0,15 Ohm für eine Goldschicht von 1300 Angström bzw. eine prozentuale Widerstandsänderung zwischen 2,3 und 0,033 gemessen. Ein gleiches Verhalten zeigte ein elektrisch polarisierbarer Grundkörper aus Triglyzin-Sulfat. In a practical embodiment, an electrically polarizable base body was chosen from Barium titanate found its polarization within a second at a thickness of 0.005 cm reversed at room temperature when a voltage of about 1 to 2 volts is applied. at a thickness of 0.05 cm a voltage of about 10 volts was required. On the same body gold layers with thicknesses between 100 and 1300 Angstroms were evaporated and the Change in resistance values measured. It was found that the change in the resistance values, both with a complete as well as with only a partial reversal of the polarization of the barium titanate was obtained in proportion to the surface charge delivered by it, where the thinner gold layers experienced the larger changes in resistance. For the circumstances a complete reversal of polarization resulted in resistance values between 25 ohms for a gold layer of 100 Angstroms and 0.15 ohms for a gold layer of 1300 Angstroms and a percentage, respectively Change in resistance measured between 2.3 and 0.033. An electric showed the same behavior polarizable body made of triglycine sulfate.

Hierzu 1 Blatt Zeichnungen1 sheet of drawings

Claims

1 21 2

for is that the mass of the metal layer is opposite

Claim: that of the ferroelectric material is very low is held, which is why it is also provided that

Transducer, in which to vaporize on an upper metal layer on the surface of the electrically polarized base of an electrically polarizable base body,
pers made of ferroelectric material A material is arranged opposite the known transducer, the charge carrier density of which is achieved by the advantage that a metal essentially single-thread degree of polarization of the ferroelectric material can be applied to a ferroelectric material, and in which a device can be changed as a semiconductor material . The manufacturing costs for applying an electric field to the io of the transducer are thereby lower. Base body to change its polarisa- At the same time its quality is improved, white! The degree of ion is provided, characterized in that the material on the surface of the layer and the ferroelectric material in the electrically polarizable base body (1), similar to a semiconductor material, can be a thin, vapor-deposited material. A metal layer (4) can also be used. vaporized metal layer has a significantly lower resistance level compared to a semiconductor material

dominate richly when the change of Pojarisa-

tiohsgrad the ferroelectric material for this from-20 is used, the resistance value of the on this

The invention relates to a transducer for changing the material in place. In the event of a deformation on a surface of an electrically polarizing equal, the base body made of ferroelectric material controllable by means of a metal layer lies in the order of magnitude of a material whose charge carrier is less than 1% compared to that of a dense due to the degree of polarization of the ferroelectric - ₂₅ semiconductor material. The measured value material according to the invention can be changed, and in which a converter can therefore process considerably larger currents and direction for applying an electric field to also larger current fluctuations,
the base body to change its polarization. _{Except for the} electrical resistance, it can be provided. by changing the degree of polarization of the ferro- _{electric material according to the USA.-patent specification 2791758 30} still further physical transducer of this type is the on properties of the vapor-deposited metal layer on the surface of the electrically polarizable base, so that the transducer according to the invention body arranged material can be obtained in wide range of applications, a semiconductor body, _e. As further of the one pn-over-influenceable quantities prestressed in the blocking direction come into consideration that progress contains. If the polarization degree of the case ₃₅ plantation and reflectance of light, the critical changes to the η-layer of the semiconductor body adjacent temperature and the magnetic field when About ferroelectric material then undergoes transition from the normal to the superconducting Zudie η-layer a change in their charge carrier stood in the case of a density to be addressed as a superconductor, ie there is such a shift of metal, the Hall voltage, the Mossbauer effect of the electron-hole pairs, that a second pn-over ₄₀ and the Curie temperature in the case of one is obtained as Ferrogang. This second pn junction magnetically addressed metal,
changes the cross-section effective for the passage of current. An embodiment of the inventive sectional area of the η-layer of the semiconductor body is shown in the accompanying drawing and thus its resistance value. The known shown schematically. Therein 1 denotes a measured value transducer consequently makes use of it, 45 electrically polarizable base bodies made of ferrodassembling certain semiconductor materials when an electrical material is applied, the typical thickness of the dielectric field perpendicular to its surface is 0.01 and 0.001 cm and a length and width because of the over it entire thickness acting elec- trically of 1 cm each. Barium titanate is preferably used as the ferroelectric matetric field gradient for its resistance value anrial. Can Weidern when the applied electric field, ₅ o tere materials are Triglyzin sulfate and potassium So in this case, the degree of polarization of the dihydrogen phosphate. On the lower surface of the η-layer of the semiconductor body applied ferroelek base body 1 is a thin metal layer! with bags of material that is changed. a diameter of about 6 mm vapor-deposited, on The invention is based on the object, one to which an electrical contact wire 3 is attached. to create simpler transducers of this type. 55 The metal layer 2 serves as an electrode for changing the degree of polarization of the base body 1. a further metal layer 4 in an arrangement opposite to the electrically polarizable base body, a thin, vapor-deposited material arranged on the metal layer 2. One of the two on the metal layer 4 is a metal layer. Fixed contact wires 5 are used in conjunction with If, in such a transducer, the degree of contact of the ferroelectric material fixed to the metal layer 2 changes the build-up of an electrical field in which, then despite the absence of a base body 1, it comes over during the second contact electrical Fcldgradienten in the metal layer to 65 wire, for example, with a change in a change in the charge carrier density and degree of polarization of the base body 1, which leads to a change in the physical resistance of the metal layer 4, the properties of the metal layer decrease. A prerequisite for this.