SU789691A1 - Apparatus for measuring surface temperature distribution - Google Patents

Description

I

The invention relates to radiation pyrometry and can be used to measure the temperature distribution over a surface, e.g., semiconductor products.

A heat flow resistor is known that contains a heat-absorbing element and two heat sinks, said element being made in the form of a wafer of material that is deformed relative to the initial state, retains the deformable state in a certain temperature range and returns to its original state with a certain change in temperature IJ .

The disadvantage of this resistor is the low measurement accuracy, due to the low resolution of the heat transfer element.

A device is known that implements a method for measuring the temperature distribution dissipated by a heat source, which materializes the space surrounding the heat source by introducing a heat-absorbing element, for example a mesh, made of a material with high heat conductivity, and performing pyletermography in

infrared spectrum over the entire surface of the grid 2.

The disadvantage of this device is the low measurement accuracy,

5 due to the discreteness of the aneshea temperature field by the absorbing element / made in the form of a grid.

The closest in technical essence to the present invention is a device for measuring the surface temperature distribution, containing an optical system that collects infrared radiation and directs it to a thermoelastic element, for example

tS is a layer of liquid placed in a cuvette, deformable depending on the intensity of this radiation, as well as a thermal deformation recording unit.

20 A significant disadvantage of this device is the low measurement accuracy due to the influence of external influences (shock vibration, acoustic waves) on the distribution

Claims (3)

25 fields of surface displacements of a thermoelastic element, besides temperature resolution influences the measurement accuracy, due to the fluid properties of the thermoelectric element. The purpose of the invention is to improve the accuracy of measuring the temperature distribution of a surface by increasing the resolution of the device. This goal is achieved by the fact that, in a device for measuring surface temperature, containing an optical system, a thermoelastic element sensitive to infrared radiation, and a thermal deformation box, this thermoelastic element is made of a ferroelectric material with a low-domain structure and placed in a heat chamber. The drawing shows a diagram of the proposed device. A device for measuring the surface temperature distribution contained an optical system 1, a thermoelastic element 2 placed in a heat chamber 3, a thermal deformation field recording unit 4, which includes a source of 5 monochromatic light, a turning mirror b, a beam splitter 7, a reference mirror 8, a lens 9, a hologram 10 thermoelastic element, rotating mirror 11 and lens 12. Consider the main functions performed by each of the structural elements of the device. Optical system 1 is a lens that is infrared infrared. It collects this radiation from the surface of the object. Thermoelastic element 2 is installed at the focus of system 1 and is a thin, on the order of 1 mm, ferroelectric plate with a small domain structure. Domains have a size of some tenths of a mm and have great mobility relative to each other. The heat chamber 3 makes it possible to maintain a stable temperature equal to the temperature of the Ryuri temperature (temperature of the phase transition of a ferroelectric), in which the domain mobility is maximal. The thermal deformation field detection unit 4 is an optical system formed by measuring and reference channels. The measuring channel is formed by successively installed and optically coupled source 5, a turning mirror b, a beam splitter 7, a turning mirror 11, a lens 12, a thermoelastic element 2, from which the reflected light strikes the recording element, which is a hologram 10 of thermoelastic element 2 The reference channel is formed by series-mounted and optically coupled source 5, a turning mirror b, a beam splitter 7, a reference mirror 8 from which the reflected light falls on the hologram 10. Works proposed device is as follows. Before measuring with thermal chamber 3, the temperature of the phase transition for this type of ferroelectric material is created, from which the thermoelastic element is made. Throughout the measurement, the temperature in the heat chamber 3 is kept constant, which allows for the maximum possible values of the domain mobility and thermal expansion coefficient. The optical system 1 forms a thermal image of the object, which is superimposed on the thermoelastic element 2. The distributed thermal field of the image causes a temperature-proportional distribution of the thermal deformation field of the element 2, which is visualized by the recording unit 4 as follows. The deformation of element 2 causes a change in the reflected phase of the light wave relative to the phase of this wave reflected from the undeformed thermoelastic element 2. This leads to the appearance of interference fringes on the holographic image of the thermoelastic element 2 restored by a hologram 10, which are used to judge the distribution of the field of thermal deformations which is proportional to the distribution of sex fields. In this case, the quantitative value of thermal deformation at any point of the temperature element 2 is determined by the number of interference fringes emanating from this point. Since the cost of dividing interference fringes is 0.2-0.3 microns, this provides a high sensitivity in measuring thermal deformation of thermoelastic element 2, which improves the accuracy of measuring the surface temperature of an object. Apparatus of the invention. For measuring the temperature distribution of a surface, comprising a successively installed optical system, a thermoelastic element sensitive to infrared radiation, and a unit for detecting a thermal deformation field, characterized in that, in order to increase the measurement accuracy by increasing the resolution, the device It is equipped with a heat chamber in which a thermoelastic element is installed, made of a ferroelectric material with a small-domain structure. Sources of information taken into account in the examination 1. Patent SZIA 3905228, cl. G 01 K 17/00, 1976. 2. For France of France No. 2354546, cl. G 01 K 11/00, 1977. 3. For France No. 2081937, .cl. G 01J 5/00, 1972 (prototype).