A.N. Datta

Bio: A.N. Datta is an academic researcher from University of Calcutta. The author has contributed to research in topics: Microwave engineering & Transformer. The author has an hindex of 1, co-authored 1 publications receiving 5 citations.

Application of Quarter-Wave Transformers for Precise Measurement of Complex Microwave Conductivity of Semiconductors (Short Papers)

Abstract: The utility of a quarter-wave transformer for precise measurement of complex microwave conductivity of semiconductors has been demonstrated. It has been shown for a chosen conductivity of 9 /spl Omega//spl dot/cm that the improvement in measurement accuracy is nearly by a factor of 3 over the conventional reflection measurement using a Teflon transformer.

A free-space method for measurement of complex permittivity of silicon wafers at microwave frequencies

Abstract: A non-destructive, non-contact technique has been developed to characterize p-type and n-type silicon semiconductor wafers at microwave frequencies. The measurement system consists of a pair of spot-focusing horn lens antennas, mode transitions, coaxial cables and a vector network analyser (VNA). In this paper, the free-space reflection and transmission coefficients, S/sub 11/ and S/sub 21/, for a normally incident plane wave, are measured for a silicon wafer sandwiched between two teflon plates which are quarter-wavelength at midband. The actual reflection and transmission coefficient, S/sub 11/ and S/sub 21/, of the silicon wafers are calculated from the measured S/sub 11/ and S/sub 21/ of the teflon plate-silicon wafer-teflon plate assembly in which the complex permittivity and thickness of the teflon plates are known. From the complex permittivity, the resistivity and conductivity can be obtained. Results are reported in the frequency range of 11-12.5 GHz. The values of the dielectric constant obtained were close to published values for silicon wafers.

Microwave Characterization of Silicon Wafer Using Rectangular Dielectric Waveguide

Abstract: A non-destructive and easy to use method is presented to characterize p-type and n-type silicon semiconductor wafers using a rectangular dielectric waveguide measurement (RDWG) system The measurement system consists of a vector network analyzer (VNA), a pair of coaxial cable, coaxial to waveguide adapter and dielectric-filled standard gain horn antenna In this method, the reflection and transmission coefficients, S11 and S21, were measured for silicon wafer sandwiched between the two Teflon, the dielectric that filled the standard gain horn antenna It was observed that, the dielectric constant of the silicon wafers are relatively constant, varying slightly over the frequency range of 9 to 12 GHz The loss factor, loss tangent and conductivity of the doped wafers are higher than the undoped type

A free-space measurement of complex permittivity of doped silicon wafers using transmission coefficient at microwave frequencies

Abstract: A contactless and non-destructive method is presented to characterize p-type and n-type silicon semiconductor wafers using a spot-focused free-space measurement system. In this method, the free-space reflection and transmission coefficients, S 11 and S 21 , are measured for silicon wafer sandwiched between two teflon plates which are quarter-wavelength at mid-band. The actual reflection and transmission coefficient, S 11 and S 21 of the silicon wafers are then calculated from the measured S 11 and S 21 by using ABCD matrix transformation in which the complex permittivity and thickness of the teflon plates are known. Complex permittivity are computed using only the transmission coefficient, S 21 . From the complex permittivity, the resistivity and conductivity can be obtained. Results are reported in the frequency range of 9–12.5 GHz. The dielectric constant obtained were close to published values for silicon wafers and the resistivities agree well with that measured by other conventional method.

Accuracy considerations for dielectric measurements of semiconductor wafers using free space microwave measurement system in 8-13 GHz range

Abstract: An algorithm using only transmission measurements to calculate the complex permittivity of p-type and n-type silicon semiconductor wafers using a spot-focused free-space measurement system was developed The dielectric constant obtained was close to published values for silicon wafers The errors associated with the measurement of the complex permittivity values are discussed, and comparisons between the measured and calculated magnitude and phase of the forward reflection and transmission coefficients are presented In this method, the free-space reflection and transmission coefficients, S/sub 11/ and S/sub 21/, are measured for a silicon wafer sandwiched between two teflon plates which are quarter-wavelength at midband The actual reflection and transmission coefficient, S/sub 11/ and S/sub 21/ of the silicon wafers are then calculated from the measured S/sub 11/ and S/sub 21/ by using ABCD matrix transformation in which the complex permittivity and thickness of the teflon plates are known Results are reported in the frequency range of 8-125 GHz

Materials with required dielectric properties: Computational development and production of polymer‐ceramic composites

Abstract: Many applications in wireless communication, microelectronics, and microwave power engineering rely on dielectrics with particular dielectric properties. This article proposes an original approach that can be used for producing materials with required complex permittivity. The technique is based on an inverted power-law mixing rule model computing volume fractions in which three or more prime materials should be taken to get in the resulting homogeneous mixture the required dielectric properties. Functionality of the approach is demonstrated by production of composites from a polymer matrix (polymethyl methacrylate) and two inorganic fillers (silicon and alumina). The composites are made by mechanically mixing the powders and axially hot-pressing and cooling the mixture. Complex permittivity of the samples is measured by a split-post resonator method. Experimental data on dielectric properties of the samples help calibrate the technique; for the used powders, the Looyenga power-law model is found to be most adequate. In the produced samples, the target values of dielectric constant are reached with a higher precision than the ones of the loss factor; however, analysis of the production process and error propagation in the computations suggest that deviations of the resultant complex permittivity fall in the anticipated ranges. Features and issues of both computational and production parts of the technique are finally discussed. POLYM. ENG. SCI., 58:319–326, 2018. VC 2017 Society of Plastics Engineers