High-frequency wafer-probing techniques

1987 ◽  
Vol 65 (8) ◽  
pp. 850-855 ◽  
Author(s):  
G. Rabjohn ◽  
J. Wolczanski ◽  
R. Surridge
Keyword(s):  
Analog Circuits ◽  
High Frequency ◽  
High Speed ◽  
Return Loss ◽  
Frequency Measurement ◽  
Microwave Frequencies ◽  
Wafer Probing ◽  
Coaxial Lines ◽  
Monolithic Components ◽  
Better Than

High-speed digital and microwave circuits have traditionally been tested by dicing wafers and mounting chips into high-frequency test carriers. This process is expensive, time consuming, and destructive. Methods of high-frequency measurement at the wafer stage are very desirable; for example, for wafer mapping, but conventional needle probes cannot be used because of their parasitics. New probe structures based on fine coaxial lines, vertically mounted microstrip lines, and tapered coplanar lines have been reported.For measurement at microwave frequencies (2–20 GHz), we have developed a geometry of a coplanar wave-guide probe that gives better than 10 dB return loss. Individual monolithic components can easily be measured and modelled for inclusion in a circuit simulation.For the measurement of digital circuits, especially those requiring several high-speed signal lines, we have used proprietary microstrip probes. Satisfactory operation up to about 2 Gbit∙s−1 has been observed, the upper bit rate being restricted by the inductance of the probe tip.Microwave-frequency and time-domain measurements of both types of probes have been made and will be discussed. Additionally, examples of the use of these probes for on-wafer measurements of digital and analog circuits will be given.

scholarly journals Logarithmic Slots Antennas Using Substrate Integrated Waveguide

2015 ◽  
Vol 2015 ◽  
pp. 1-11 ◽  
Author(s):  
Jahnavi Kachhia ◽  
Amit Patel ◽  
Alpesh Vala ◽  
Romil Patel ◽  
Keyur Mahant
Keyword(s):  
Dielectric Constant ◽  
High Frequency ◽  
Return Loss ◽  
High Gain ◽  
Substrate Integrated Waveguide ◽  
High Frequency Structure Simulator ◽  
High Gain Antenna ◽  
X Band ◽  
New Generation ◽  
Better Than

This paper represents new generation of slotted antennas for satellite application where the loss can be compensated in terms of power or gain of antenna. First option is very crucial because it totally depends on size of satellite so we have proposed the high gain antenna creating number of rectangular, trapezoidal, and I shape slots in logarithm size in Substrate Integrated Waveguide (SIW) structure. The structure consists of an array of various shape slots antenna designed to operate in C and X band applications. The basic structures have been designed over a RT duroid substrate with dielectric constant of 2.2 and with a thickness of 0.508 mm. Multiple slots array and shape of slot effects have been studied and analyzed using HFSS (High Frequency Structure Simulator). The designs have been supported with its return loss, gain plot, VSWR, and radiation pattern characteristics to validate multiband operation. All the proposed antennas give gain more than 9 dB and return loss better than −10 dB. However, the proposed structures have been very sensitive to their physical dimensions.

scholarly journals Design of RF MEMS based switch matrix for space applications

2013 ◽  
Vol 11 ◽  
pp. 143-152 ◽  
Author(s):  
S. Di Nardo ◽  
P. Farinelli ◽  
T. Kim ◽  
R. Marcelli ◽  
B. Margesin ◽  
...  
Keyword(s):  
Design Process ◽  
High Frequency ◽  
Return Loss ◽  
Rf Mems ◽  
Space Applications ◽  
Simulated Performance ◽  
Benes Network ◽  
Matrix Design ◽  
Better Than ◽  
Ku Band

Abstract. RF MEMS based switch matrices have several advantages compared to the mechanical or solid-state switch based ones for space applications. They are compact, light and less lossy with a high linearity up to high frequency. In this work, a 12 × 12 switch matrix with RF MEMS and LTCC technologies is presented based on the planar Beneš network. The simulated performance of the 12 × 12 switch matrix is below −12 dB IL (Insertion Loss) up to C band and −15 dB RL (Return Loss) up to Ku band. Moreover, it has a good isolation better than −50 dB. A 4 × 4 switch matrix with the same design process and technologies is fabricated and measured to verify the 12 × 12 switch matrix design process. The measured performance agrees very well to the simulations.

scholarly journals Compact Ultra-Wideband Phase Inverter Using Microstrip-CPW-Slotline Transitions

Electronics ◽  
2021 ◽  
Vol 10 (3) ◽  
pp. 252
Author(s):  
Wahab Mohyuddin ◽  
Gwan Hui Lee ◽  
Dong Sik Woo ◽  
Hyun Chul Choi ◽  
Kang Wook Kim
Keyword(s):  
Return Loss ◽  
Coplanar Waveguide ◽  
Impedance Matching ◽  
Ultra Wideband ◽  
Frequency Bandwidth ◽  
Microwave Frequencies ◽  
Phase Inverter ◽  
Field Transformation ◽  
Phase Deviation ◽  
Better Than

A planar ultra-wideband phase inverter, which consists of a series of transitions between microstrip, coplanar waveguide, and slotline, is designed and implemented. This compact-sized phase inverter can be used to generate wideband 180° phase differential signals, especially at high microwave frequencies up to millimeter-waves. The design is based on the impedance matching and smooth field transformation between the transitional stages. The fabricated transition has dimensions of 7.36 mm × 5.08 mm, and provides ultra-wide frequency bandwidth from 13 GHz to 38 GHz with low insertion loss of better than 2 dB within ±5° phase deviation and with return loss of greater than 10 dB.

The Radio Probe™: A New Measurement Tool for High Speed Integrated Circuits

2005 ◽  
Author(s):  
Mark Kimball
Keyword(s):  
Integrated Circuits ◽  
Integrated Circuit ◽  
High Speed ◽  
Attenuation Factor ◽  
Cost Effective ◽  
Frequency Measurement ◽  
Single Frequency ◽  
Measurement Tool ◽  
Probe Design ◽  
Differential Measurement

Abstract This article presents a novel tool designed to allow circuit node measurements in a radio frequency (RF) integrated circuit. The discussion covers RF circuit problems; provides details on the Radio Probe design, which achieves an input impedance of 50Kohms and an overall attenuation factor of 0 dB; and describes signal to noise issues in the output signal, along with their improvement techniques. This cost-effective solution incorporates features that make it well suited to the task of differential measurement of circuit nodes within an RF IC. The Radio Probe concept offers a number of advantages compared to active probes. It is a single frequency measurement tool, so it complements, rather than replaces, active probes.

scholarly journals A balanced-to-balanced directional coupler based on branch-slotline coupled structure

Frequenz ◽  
2020 ◽  
Vol 74 (11-12) ◽  
pp. 427-433
Author(s):  
Yaxin Liu ◽  
Feng Wei ◽  
Xiaowei Shi ◽  
Cao Zeng
Keyword(s):  
Directional Coupler ◽  
Return Loss ◽  
Design Method ◽  
Differential Mode ◽  
Arbitrary Power ◽  
Measurement Results ◽  
Transition Structures ◽  
Coupled Structures ◽  
Better Than ◽  
Good Agreement

AbstractIn this paper, a balanced-to-balanced (BTB) branch-slotline directional coupler (DC) is firstly presented, which can realize an arbitrary power division ratios (PDRs). The coupler is composed by microstrip-to-slotline (MS) transition structures and branch-slotline coupled structures. The single-ended to balanced-ended conversion is simplified and easy to implemented by the MS transition structures, which intrinsically leads to the differential-mode (DM) transmission and common-mode (CM) suppression. Moreover, the different PDRs which are controlled by the widths of branch-slotlines can be achieved. In order to verify the feasibility of the proposed design method, two prototype circuits of the proposed coupler with different PDRs are fabricated and measured. The return loss and the isolation of two designs are all better than 10 dB. Moreover, the CM suppressions are greater than 35 dB. A good agreement between the simulation and measurement results is observed.

scholarly journals Chance or Necessity—The Fungi Co−Occurring with Formica polyctena Ants

Insects ◽  
2021 ◽  
Vol 12 (3) ◽  
pp. 204
Author(s):  
Igor Siedlecki ◽  
Michał Gorczak ◽  
Alicja Okrasińska ◽  
Marta Wrzosek
Keyword(s):  
Molecular Identification ◽  
High Frequency ◽  
Its Rdna ◽  
The Other ◽  
Formica Polyctena ◽  
Ant Nests ◽  
Mutualistic Fungi ◽  
The Tropics ◽  
High Diversity ◽  
Better Than

Studies on carton nesting ants and domatia−dwelling ants have shown that ant–fungi interactions may be much more common and widespread than previously thought. Until now, studies focused predominantly on parasitic and mutualistic fungi–ant interactions occurring mostly in the tropics, neglecting less−obvious interactions involving the fungi common in ants’ surroundings in temperate climates. In our study, we characterized the mycobiota of the surroundings of Formica polyctena ants by identifying nearly 600 fungal colonies that were isolated externally from the bodies of F. polyctena workers. The ants were collected from mounds found in northern and central Poland. Isolated fungi were assigned to 20 genera via molecular identification (ITS rDNA barcoding). Among these, Penicillium strains were the most frequent, belonging to eight different taxonomic sections. Other common and widespread members of Eurotiales, such as Aspergillus spp., were isolated very rarely. In our study, we managed to characterize the genera of fungi commonly present on F. polyctena workers. Our results suggest that Penicillium, Trichoderma, Mucor, Schwanniomyces and Entomortierella are commonly present in F. polyctena surroundings. Additionally, the high diversity and high frequency of Penicillium colonies isolated from ants in this study suggest that representatives of this genus may be adapted to survive in ant nests environment better than the other fungal groups, or that they are preferentially sustained by the insects in nests.

scholarly journals Band notched self complementaryultra wideband antenna for wireless applications

2018 ◽  
Vol 7 (2.8) ◽  
pp. 529 ◽  
Author(s):  
Ch Ramakrishna ◽  
G A.E.Satish Kumar ◽  
P Chandra Sekhar Reddy
Keyword(s):  
High Frequency ◽  
Return Loss ◽  
Wide Band ◽  
Ultra Wideband ◽  
Impedance Bandwidth ◽  
Relative Dielectric Permittivity ◽  
Frequency Range ◽  
Ground Structure ◽  
Wireless Applications ◽  
Patch Edge

This paper presents a band notched WLAN self complementaryultra wide band antenna for wireless applications. The proposed antenna encounters a return loss (RL) less than -10dB for entire ultra wideband frequency range except band notched frequency. This paper proposes a hexagon shape patch, edge feeding, self complementary technique and defective ground structure. The antenna has an overall dimensionof 28.3mm × 40mm × 2mm, builton  substrate FR4 with a relative dielectric permittivity 4.4. And framework is simulated finite element method with help of high frequency structured simulator HFSSv17.2.the proposed antenna achieves a impedance bandwidth of 8.6GHz,  band rejected WLAN frequency range 5.6-6.5 GHz with  vswr is less than 2.

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