Millimeter-Wave Characterization of FaAs Devices and IC's
Abstract
Coplanar waveguide transmission line (CPW) passive probes have become very popular for on-wafer characterization of integrated circuits. Since this transmission line has all conductors on one side of the substrate, it is a low parasitic medium for transmission from the input connector to the device under test. The entire line can be formed with one mask step and does not require backside metalization or via holes. Since the CPW formed on a semi-insulating substrate (e.g.GaAs) has a characteristic impedance which only depends on the center conductor width-to-ground gap, the impedance which only depends on the center conductor width-to-ground gap, the impedance can easily be changed. We have improved upon our ultra-short pulse generating capabilities with highly optimized non-linear transmission lines incorporated into the design of very wide-bandwidth electrical samples and also into an integrated circuit directional bridge. Since these integrated circuits are small, they can be mounted directly on an IC probe tip. This capability, by bringing the measurement instrument into contact with the circuit to be tested almost completely solves the interconnect losses. By placing the MMICs in an alumina tip package, we are able to measure s-parameters up to 85 GHz. Above 100 GHz, the parasitics of the connection between the MMIC samplers and the alumina probe tip become intolerable and the alumina tip must be eliminated. Since the GaAs IC cannot be flexed, we have developed a parallelogram flexure probe which will allow a controlled normal force to be applied to the tip. As a first goal, we decided to develop a through-line GaAs probe which will allow repeatable measurement at microwave frequencies.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jun 01, 1991
- Accession Number
- ADA237843
Entities
People
- David M. Bloom
Organizations
- Stanford University