Query: The reliability of planar GaAs Schottky diodes

Candidate papers:

abstract: Planar GaAs Schottky barrier mixer diodes are now being used in a variety of applications at millimeter and submillimeter wavelengths. Since these devices are being considered for space applications, device reliability is a critical issue. This paper presents first results from accelerated life testing of planar mixer diodes. THEORY OF ACCELERATED LIFE TESTING Accelerated life testing is the application of some stress to the device under test in order to shorten its time to failure. In this study on planar gallium arsenide Schottky diodes, the applied stress has been chosen to be elevated temperature. Various studies on semiconductor devices have found that the reaction rate of the physical or chemical process that causes failure is related to temperature as given by the following Arrhenius equation [1]
author_names: Jodi L Bowers
title: The reliability of planar GaAs Schottky diodes
venue: International Conference on Infrared and Millimeter Waves
year: 1992

abstract: A previously reported technology that allows for the fabrication of semiconductor devices based on quartz (or other dissimilar substrates) has resulted in state of the art mixer performance at frequencies up to 640 GHz. The present work will discuss the procedure that has been used to quantify the reliability of such devices for space borne missions. A number of accelerated lifetime tests have been conducted. It is concluded that these devices exhibit lifetimes that are consistent with other GaAs devices for space applications. Our accelerated lifetime data, analyzed with the Arrhenius lognormal model, predict a room temperature MTTF on the order of 10 hours, a value that is comparable to conventional high frequency planar Schottky diodes. This result demonstrates that the use of an appropriate epoxy to obtain GaAs devices on quartz substrates does not reduce the lifetime of the devices.
author_names: Robert Lin

A Pease

Robert J Dengler

D A Humphrey

T H Lee

Sammy Kayali
title: QUARTZ BASED GaAs SCHOTTKY DIODES LIFETIME AND FAILURE ANALYSIS
year: 2009

abstract: We have developed a reliable, high performance, batch processed, GaAs tantalum Schottky diode (with a gold overlayer) and native oxide passivated junction1in a quasi planar configuration, Varactors and mixers have been fabricated with near ideal characteristics and state of the art performance. Typically, they exhibit, at 0 V, a junction capacitance near 0.1 pF and a cutoff frequency in excess of 700 GHz when measured at 55 GHz. In a paramp application pumped at 101 GHz, and a signal frequency of 35 GHz, we have obtained a noise figure of 3.5 dB, a gain of 17 dB, and a bandwidth of 600 MHz. When used as frequency doublers (50 100 GHz) and triplers (35 105 GHz) we have realized better than 25 percent efficiency. As mixers, atXband, we achieved a single sideband noise figure of 6 dB and the diodes are typically able to sustain short pulse energy (1.5 x 10 9s) of up to 4.5 ergs with no performance degradation. Reliability tests results to date indicate a MTBF of better than 108h at 100degC and greater than 105h at 200degC. In a commercial application of paramps (3.7 4.2 GHz) these diodes have successfully completed 2.5 million operational varactor hours with no performance degradation.
author_names: Joseph A Calviello

J L Wallace
title: Performance and reliability of an improved high temperature GaAs Schottky junction and native oxide passivation
venue: IEEE Transactions on Electron Devices
year: 1977

abstract: Planar GaAs Schottky diodes will be utilized for all of the LO chains on the HIPI instrument for the Herschel Space Observatory. A better understanding of device degradation mechanisms is desirable in order to specify environmental and operational conditions that do not reduce device life times. Failures and degradation associated with ESD (Electrostatic Discharge) high temperatures, DC currents and RF induced current and heating have been investigated. The goal is to establish a procedure to obtain the safe operating range for a given frequency multiplier.
author_names: Frank Maiwald

Erich Schlecht

Robert Lin

John S Ward

John C Pearson

Peter H Siegel

Imran Mehdi
title: Reliability of Cascaded THz Frequency Chains with Planar GaAs Circuits
year: 2004

abstract: Impact ionization in GaAs based planar Gunn diodes is studied through electroluminescence (EL) analysis with the aim of reducing its magnitude by means of contact design and shaping, and thus enhance device performance and reliability. Designs in which the diode ohmic anode has an overhanging Schottky extension (composite anode contact) are shown to result in a significantly reduced amount of impact ionization, as compared with a simple ohmic contact design. The EL results are consistent with Monte Carlo simulations, which show a reduced impact ionization in composite anode contact devices due to a reduced electron density beneath the anode Schottky extension that, on the one hand, weakens the Gunn domain electric field and softens its variations near the anode edge, and, on the other hand, reduces the number of electrons capable of generating holes by impact ionization. A comparison between standard and composite anode contact approaches in terms of radio frequency operation of the devices is made showing oscillations up to 109 GHz with an output power of 5 dBm in devices featuring the composite anode contact and no oscillations from all ohmic contact devices. The findings reported in this paper may be useful not only for the design and the fabrication of planar Gunn diodes but also for other devices such as high electron mobility transistors where impact ionization can result in reliability limitations.
author_names: Miguel Montes

Geoffrey Dunn

Andreas Stephen

Ata Khalid

Chen Li

David R S Cumming

Chris Oxley

Richard Hopper

Martin Kuball
title: Reduction of Impact Ionization in GaAs Based Planar Gunn Diodes by Anode Contact Design
venue: IEEE Transactions on Electron Devices
year: 2012

abstract: A GaAs planar airbridged Schottky (PAS) diode process has been developed for insertion in high performance circuits at millimeter wave frequencies and beyond. The PAS diodes have shown a very low resistance, accompanied by low capacitance values resulting from the small anode geometry and optimization of the diode resistance. The process is developed on 4" GaAs wafers and show diode yield of >95% per wafer. The reliability of the junction is also discussed with an elevated 200 degrees thermal cycle test over a period of 24 hours showing no change in diode parameters such as ideality factor and breakdown voltage.
author_names: Hooman Kazemi

Lan Tran

D S Deakin

Jonathan Hacker

Chanh Nguyen
title: Highly Reliable GaAs Planar Airbridged Schottky Diodes for Flight Qualified Millimeter wave Circuits
year: 2006

abstract: Impact ionisation in GaAs based planar Gunn diodes is studied through electroluminescence analysis with the aim of reducing its magnitude by means of contact design and shaping and thus enhance device performance and reliability. Designs in which the diode ohmic anode has an overhanging Schottky extension (composite anode contact) are shown to result in a significantly reduced amount of impact ionisation compared to a simple ohmic contact design. The electroluminescence results are consistent with Monte Carlo simulations which show a reduced impact ionisation in composite anode contact devices due to a reduced electron density beneath the anode Schottky extension that, on the one hand, weakens the Gunn domain electric field and softens its variations near the anode edge, and, on the other hand, reduces the number of electrons capable of generating holes by impact ionisation. A comparison between standard and composite anode contact approaches in terms of RF operation of the devices is made showing oscillations up to 109 GHz with an output power of 5 dBm in devices featuring the composite anode contact and no oscillations from all ohmic contact devices. The findings reported in this work may be useful not only for the design and fabrication of planar Gunn diodes, but also for other devices such as HEMTs where impact ionisation can result in reliability limitations.
author_names: Miguel Montes

Geoffrey Dunn

Andreas Stephen

Ata Khalid

Changping Li

David R S Cumming

Chris Oxley

Harriet A Hopper

Martin Kuball
title: Kuball, M. (2012) Reduction of Impact Ionization in GaAs Based Planar Gunn Diodes by Anode Contact Design. IEEE Transactions on Electron Devices, 59(3) 654 660. DOI: 10.1109/TED.2011.2177094
year: 2011

abstract: Fix tuned, broadband local oscillator (LO) sources to 1900 GHz have been developed for the HIFI instrument on the Herschel Space Observatory. Each LO chain consists of cascaded multipliers (doublers or triplers) being pumped with high power >100 mW) power amplifier modules in the 70 to 110 GHz frequency range. For long term mission reliability it is important to quantify the safe operating conditions for these multi pliers, especially when pumped with high input power. This paper will describe on going investigations into the ef fects of excessive reverse currents in Schottky diodes along with presenting a methodology for determining safe bias conditions for a given multiplier.
author_names: Frank Maiwald

Erich Schlecht

John S Ward

Robert Lin

Rosa Leon

John C Pearson

Imran Mehdi
title: Design and operational considerations for robust planar GaAs varactors: A reliability study
year: 2003

abstract: Significant improvements in the reliability as well as yield and reproducibility of GaAs planar doped barrier (PDB) microwave detector diodes have been achieved by substituting carbon doped acceptor regions in place of conventional beryllium acceptor dopant. The superior characteristics of the C doped PDB diodes are thought to be related to the hyperabrupt and stable carbon acceptor doping spikes (10 60 A) obtained in the n/sup i p/sup i n/sup doping profile grown by molecular beam epitaxy (MBE) Mesa geometry PDB diodes (10 20 micron diameter) in micropill packages were RF tested at 10 and 35 GHz. Excellent tangential sensitivity up to 58 dBm was measured with a detector video impedance of 2 50 kohms depending upon barrier height. The electrostatic discharge (ESD) failure threshold voltages were found to be much higher for the PDB diodes (3500 V) in comparison to Schottky detector diodes (300 V)<ETX>
author_names: Roger J Malik

Yoginder Anand

Miroslav Micovic

Michael Geva

R W Ryan
title: Performance and reliability characteristics of GaAs planar doped barrier detector diodes using carbon doped acceptor spikes grown by molecular beam epitaxy
venue: Proceedings of IEEE/Cornell Conference on Advanced Concepts in High Speed Semiconductor Devices and Circuits
year: 1993

abstract: Planar doped barrier (PDB) diodes with extremely low barrier heights and highly asymmetric I V characteristics have been developed using MBE (molecular beam epitaxy) grown GaAs material. The authors report on the RF performance of these devices and discuss the significant advantages offered by PDB devices over conventional Schottky diodes for mixer and detector applications at both microwave and millimeter wave frequencies. These advantages include reduced mixer driver levels, reduced low frequency noise generation, improved detector tangential sensitivity and general reliability improvements as a result of the burnout performance.<ETX>
author_names: I Dale

Angus Condie

S Neylon

Michael J Kearney
title: Planar doped barrier mixer and detector diodes as alternatives to Schottky diodes for both microwave and millimetre wave applications
venue: IEEE MTT S International Microwave Symposium Digest
year: 1989