Integrated GaAs Diode Technology for Millimeter and Submillimeter-wave Components and Systems

2000 ◽  
Vol 631 ◽  
Author(s):  
Thomas W. Crowe ◽  
Jeffrey L. Hesler ◽  
William L. Bishop ◽  
Willie E. Bowen ◽  
Richard F. Bradley ◽  
...  
Keyword(s):  
Wafer Bonding ◽  
Room Temperature ◽  
Flip Chip ◽  
Quartz Substrate ◽  
Submillimeter Wave ◽  
Bonding Process ◽  
Circuit Performance ◽  
Embedding Impedance ◽  
Compact Range ◽  
The Cost

ABSTRACTGaAs Schottky barrier diodes remain a workhorse technology for submillimeter-wave applications including radio astronomy, chemical spectroscopy, atmospheric studies, plasma diagnostics and compact range radar. This is because of the inherent speed of these devices and their ability to operate at room temperature. Although planar (flip-chip and beam-lead) diodes are replacing whisker contacted diodes throughout this frequency range, the handling and placement of such small GaAs chips limits performance and greatly increases component costs. Through the use of a novel wafer bonding process we have fabricated and tested submillimeter-wave components where the GaAs diode is integrated on a quartz substrate along with other circuit elements such as filters, probes and bias lines. This not only eliminates the cost of handling microscopically small chips, but also improves circuit performance. This is because the parasitic capacitance is reduced by the elimination of the GaAs substrate and the electrical embedding impedance seen by the diodes is more precisely controlled. Our wafer bonding process has been demonstrated through the fabrication and testing of a fundamental mixer at 585 GHz (Tmix < 1200K) and a 380 GHz subharmonically pumped mixer (Tmix < 1000K). This paper reviews the wafer bonding process and discusses how it can be used to greatly improve the performance and manufacturability of submillimeter-wave components.

Low Temperature Wafer Level Bonding Using Benzocyclobutene Adhesive Polymers

2012 ◽  
Vol 2012 (DPC) ◽  
pp. 1-24
Author(s):  
Michael Gallagher ◽  
Jong-Uk Kim ◽  
Eric Huenger ◽  
Kai Zoschke ◽  
Christina Lopper ◽  
...  
Keyword(s):  
Low Temperature ◽  
Wafer Bonding ◽  
Flip Chip ◽  
Bonding Temperature ◽  
Bonding Process ◽  
Curing Temperature ◽  
Wafer Level ◽  
Mechanical Adhesion ◽  
3D Stacking ◽  
Dry Etch

3D stacking, one of the 3D integration technologies using through silicon vias (TSVs), is considered as a desirable 3D solution due to its cost effectiveness and matured technical background. For successful 3D stacking, precisely controlled bonding of the two substrates is necessary, so that various methods and materials have been developed over the last decade. Wafer bonding using polymeric adhesives has advantages. Surface roughness, which is critical in direct bonding and metal-to-metal bonding, is not a significant issue, as the organic adhesive can smooth out the unevenness during bonding process. Moreover, bonding of good quality can be obtained using relatively low bonding pressure and low bonding temperature. Benzocyclobutene (BCB) polymers have been commonly used as bonding adhesives due to their relatively low curing temperature (~250 °C), very low water uptake (&lt;0.2%), excellent planarizing capability, and good affinity to Cu metal lines. In this study, we present wafer bonding with BCB at various conditions. In particular, bonding experiments are performed at low temperature range (180 °C ~ 210 °C), which results in partially cured state. In order to examine the effectiveness of the low temperature process, the mechanical (adhesion) strength and dimensional changes are measured after bonding, and compared with the values of the fully cured state. Two different BCB polymers, dry-etch type and photo type, are examined. Dry etch BCB is proper for full-area bonding, as it has low degree of cure and therefore less viscosity. Photo-BCB has advantages when a pattern (frame or via open) is to be structured on the film, since it is photoimageable (negative tone), and its moderate viscosity enables the film to sustain the patterns during the wafer bonding process. The effect of edge beads at the wafer rim area and the soft cure (before bonding) conditions on the bonding quality are also studied. Alan/Rey ok move from Flip Chip and Wafer Level Packaging 1-6-12.

A Method of MEMS Package Using Local Laser Bonding

2011 ◽  
Vol 328-330 ◽  
pp. 1313-1316
Author(s):  
Li Cheng ◽  
Yi Xin Zhang ◽  
Jiao Xu ◽  
Ming Yan
Keyword(s):  
Room Temperature ◽  
Micro Electro Mechanical System ◽  
Bonding Process ◽  
Chip Surface ◽  
Laser Bonding ◽  
Negative Effect ◽  
Low Temperature Bonding ◽  
The Cost ◽  
Conventional Laser

The negative effect of the conventional laser bonding caused by high temperature has been analyzed in the Si-glass bonding process. A new method which is the combination of chip surface activated pre-bonding and laser bonding has been proposed. The method has been used for Micro Electro Mechanical System package experiment. The process is: firstly, a hydrophilic surface was formed by using a special chemical method. Secondly, Si and glass were pre-bonded at room temperature. Finally, the laser with the wavelength of 1.070 μm, spot diameter of 480 μm, power of 70 W was local heated by the laser. This method achieves low-temperature bonding without external press. And the tensile test also shows that the strength of sample bonding reaches 2.8 MPa~3.2 MPa. So it not only ensures the quality of MEMS chip, but also reduces the cost of the package.

ZoneBOND Thin Wafer Support Process for Wafer Bonding Applications

2010 ◽  
Vol 7 (3) ◽  
pp. 138-142 ◽  
Author(s):  
Jeremy McCutcheon ◽  
Robert Brown ◽  
JoElle Dachsteiner
Keyword(s):  
Wafer Bonding ◽  
Room Temperature ◽  
Bonding Process ◽  
Temporary Bonding ◽  
Higher Temperature

The ZoneBOND process has been developed as an alternative temporary bonding process that bonds at an acceptable temperature (usually less than 200°C), survives through higher-temperature processes, and then debonds at room temperature. The technology utilizes standard silicon or glass carriers and current thermoplastic adhesives developed by Brewer Science, Inc.

(ECS Meeting PRiME 2020) High TEC copper to connect copper bond pads for low temperature wafer bonding

2020 ◽  
Author(s):  
Anh Van Nhat Tran ◽  
Kazuo Kondo ◽  
Tetsuji Hirato
Keyword(s):  
Wafer Bonding ◽  
Room Temperature ◽  
Three Dimensional ◽  
Copper Surface ◽  
Bonding Process ◽  
3D Integration ◽  
High Thermal Expansion ◽  
Lower Temperature ◽  
Bond Pads ◽  
High Thermal Expansion Coefficient

Copper to copper wafer hybrid bonding is the most promising technology for three-dimensional (3D) integration. In the hybrid bonding process, two silicon wafers are aligned and contacted. At room temperature, these aligned copper pads contain radial-shaped nanometer-sized hollows due to the dishing effect induced by chemical-mechanical polishing (CMP). These wafers are annealed for copper to expand and connect upper and lower pads. This copper expansion is key to eliminate the radial-shaped hollows and make copper pads contacted. Therefore, in this research, we investigated the new high thermal expansion coefficient (TEC) electrodeposited copper to eliminate dishing hollows at lower temperature than that with conventional copper using the combination of new additive A and three other additives. The TEC of new electrodeposited copper is 25.2 x 10-6 oC-1, 46% higher than conventional copper and the calculated contact area of copper surface at 250oC with 5 nm dishing depth is 100%.

TCB Process Options to Achieve the Lowest Cost

2016 ◽  
Vol 2016 (DPC) ◽  
pp. 001277-001301
Author(s):  
Tom Strothmann
Keyword(s):  
Flip Chip ◽  
Bonding Process ◽  
Heating Rates ◽  
Fine Pitch ◽  
Key Factor ◽  
3D Assembly ◽  
Cost Calculations ◽  
Improved Performance ◽  
Memory Applications ◽  
The Cost

Thermocompression bonding enables the next generation fine pitch, 2.5D and 3D assembly technologies using Cu pillar interconnects, but to achieve widespread adoption the cost of TCB must become competitive with mass reflow processes. Stacked memory products drive the commercial volume today using TSV structures and TCB since it is the only technology able to achieve the desired stacked die construction and improved performance, but reducing the cost of assembly is still a key goal for those suppliers. In non-memory applications the choice of TCB can be driven by the bump pitch of the device or the requirement to control warpage of large die on laminate during assembly, but cost is still a key factor in the decision. The cost of a TCB process is largely driven by the UPH of the process where cost calculations are based on the cost per unit of material produced. As the UPH of a TCB process approaches 1400, the differential cost of the TCB process as compared to mass reflow becomes negligible. In the choice of a potential TCB process, special attention must be given to those processes that enable the highest UPH and the lowest cost. Processes used for TCB today can be grouped into two main categories; processes that use a pre-applied underfill and those that apply underfill after the bonding process. Underfills applied prior to bonding can be in the form of a non-conductive paste (TC-NCP) applied to a substrate or a non-conductive film applied to the wafer before dicing (TC-NCF). If underfill is applied after the bonding process, it is done as a Capillary Underfill (TC-CUF). In this case the die is underfilled in much the same way as in standard flip chip processes, but the process can be more challenging because of flux cleaning requirements and the narrower bondline of a typical TCB device. UPH is primarily driven by two factors; the range of temperature required by the bond head and the temperature ramp rate of the bond head. A process with less temperature range will have higher UPH and bond heads designed for the fastest cooling and heating rates will provide higher UPH processes. Two process options have been developed to minimize the temperature excursions required by the bond head and maximize the throughput. TC- NCF processes targeting stacked die and interposer products have been developed with throughputs approaching 2000 UPH. Substrate flux TC-CUF processes targeting assembly on laminate have been developed with throughputs that approach 2500 UPH. These two processes are expected to dominate TCB volume production moving forward as TCB enters mainstream production. This presentation will describe the methods used to achieve high throughput for both processes and the product application space appropriate for each one.

A Cost and Yield Analysis of Wafer-to-wafer Bonding

2015 ◽  
Vol 2015 (DPC) ◽  
pp. 000401-000418 ◽  
Author(s):  
Amy Palesko ◽  
Chet Palesko
Keyword(s):  
Wafer Bonding ◽  
Bonding Process ◽  
Technology Selection ◽  
Total Cost ◽  
Trade Offs ◽  
Multiple Variables ◽  
Die Bonding ◽  
Time Required ◽  
The Cost ◽  
The Impact

When a product requires the bonding of two die or wafers, there are a number of methods that may be used. Not only does the type of bonding process itself have to be selected, but it must also be determined whether the items being bonded will be in wafer or die form. This paper will focus on wafer-to-wafer bonding, which has the highest throughput compared to die-to-wafer and die-to-die bonding; it also has the potential to be the lowest cost option if proper yields are achieved. This paper will introduce the background and general pros and cons of wafer-to-wafer, die-to-wafer, and die-to-die bonding. Activity based cost modeling will be used to construct a generic flow of a wafer-to-wafer bonding process. The process flow will be divided into a series of activities, and the total cost of each activity will be identified. The cost of each activity will be determined by analyzing the following attributes: time required, amount of labor required, cost of material required (consumable and permanent), tooling cost, depreciation cost of the equipment, and yield loss associated with the activity. The model will be used to explore multiple variables that affect the total cost of the wafer-to-wafer bonding process, including: incoming wafer cost, incoming wafer defect density, time required for the dicing process, time required for the bonding process, cost of the equipment for the bonding process, and the yield of the bonding process. First, a sensitivity analysis will be conducted to determine the impact each variable has on the total cost. Then scenarios will be created to conduct trade-offs between multiple variables. Only one, generic wafer-to-wafer bonding model will be created, but there will be enough variables to accurately reflect different bonding methods in use by the industry today. Methods for bonding two wafers together will also be discussed in the paper, as well as the cost and yield issues associated with each. An example of these methods are thermo compression bonding and direct bonding. The goal of this analysis will be to understand the cost and yield drivers associated with wafer-to-wafer bonding, and to determine scenarios in which wafer-to-wafer bonding is a suitable, cost effective technology selection.

scholarly journals Longevity of Raw and Lyophilized Crude Urease Extracts

2021 ◽  
Vol 2 (2) ◽  
pp. 325-334
Author(s):  
Neda Javadi ◽  
Hamed Khodadadi Tirkolaei ◽  
Nasser Hamdan ◽  
Edward Kavazanjian
Keyword(s):  
Crude Extract ◽  
Room Temperature ◽  
Low Cost ◽  
Extraction Process ◽  
Crude Extracts ◽  
Simple Extraction ◽  
Commercial Applications ◽  
Stable Source ◽  
The Stability ◽  
The Cost

The stability (longevity of activity) of three crude urease extracts was evaluated in a laboratory study as part of an effort to reduce the cost of urease for applications that do not require high purity enzyme. A low-cost, stable source of urease will greatly facilitate engineering applications of urease such as biocementation of soil. Inexpensive crude extracts of urease have been shown to be effective at hydrolyzing urea for carbonate precipitation. However, some studies have suggested that the activity of a crude extract may decrease with time, limiting the potential for its mass production for commercial applications. The stability of crude urease extracts shown to be effective for biocementation was studied. The crude extracts were obtained from jack beans via a simple extraction process, stored at room temperature and at 4 ℃, and periodically tested to evaluate their stability. To facilitate storage and transportation of the extracted enzyme, the longevity of the enzyme following freeze drying (lyophilization) to reduce the crude extract to a powder and subsequent re-hydration into an aqueous solution was evaluated. In an attempt to improve the shelf life of the lyophilized extract, dextran and sucrose were added during lyophilization. The stability of purified commercial urease following rehydration was also investigated. Results of the laboratory tests showed that the lyophilized crude extract maintained its activity during storage more effectively than either the crude extract solution or the rehydrated commercial urease. While incorporating 2% dextran (w/v) prior to lyophilization of the crude extract increased the overall enzymatic activity, it did not enhance the stability of the urease during storage.

scholarly journals Silicon-Quartz Microcapillary Opto-Fluidic Platform Obtained by CMOS-Compatible Die to Wafer 200 mm Dual Bonding Process

Proceedings ◽  
2018 ◽  
Vol 2 (13) ◽  
pp. 1018
Author(s):  
Giuseppe Fiorentino ◽  
Ben Jones ◽  
Sophie Roth ◽  
Edith Grac ◽  
Murali Jayapala ◽  
...  
Keyword(s):  
Adhesive Bonding ◽  
System Analysis ◽  
Quartz Substrate ◽  
Microfluidic System ◽  
Bonding Process ◽  
Microfluidic Channels ◽  
Fully Integrated ◽  
Lab On Chip ◽  
Human Blood Cells ◽  
On Chip

A composite, capillary-driven microfluidic system suitable for transmitted light microscopy of cells (e.g., red and white human blood cells) is fabricated and demonstrated. The microfluidic system consists of a microchannels network fabricated in a photo-patternable adhesive polymer on a quartz substrate, which, by means of adhesive bonding, is then connected to a silicon microfluidic die (for processing of the biological sample) and quartz die (to form the imaging chamber). The entire bonding process makes use of a very low temperature budget (200 °C). In this demonstrator, the silicon die consists of microfluidic channels with transition structures to allow conveyance of fluid utilizing capillary forces from the polymer channels to the silicon channels and back to the polymer channels. Compared to existing devices, this fully integrated platform combines on the same substrate silicon microfluidic capabilities with optical system analysis, representing a portable and versatile lab-on-chip device.

Design of the Automatic Guided Vehicle Control System Applied to Automotive Logistics

2014 ◽  
Vol 644-650 ◽  
pp. 381-384
Author(s):  
Xin Zhang ◽  
Hao Zhou ◽  
Guo Song Liu
Keyword(s):  
Control System ◽  
Absolute Error ◽  
Vehicle Control ◽  
Test Results ◽  
Circuit Performance ◽  
Automatic Driving ◽  
Automatic Guided Vehicle ◽  
Distribution Logistics ◽  
Auto Parts ◽  
The Cost

In order to improve the efficiency of auto parts distribution logistics, to lower the cost of auto production in transportation logistics, and to reduce accidents, in this paper it is designed that an automatic guided vehicle control system to replace the manned tractors in the distribution sites. The system is equipped with an infrared homing device that can ensure the automated guided vehicle (AGV) along a predetermined route automatic driving at a given distribution information, without the needs to manually guided. Test results show that the circuit performance of AGV control system is stable to ensure the accuracy of the tracking in the practical application, and the mean absolute error of the tracking is less than 0.04m.

Room-Temperature Wafer Bonded Multi-Junction Solar Cell Grown by Solid State Molecular Beam Epitaxy

MRS Advances ◽  
2016 ◽  
Vol 1 (43) ◽  
pp. 2907-2916 ◽  
Author(s):  
Shulong Lu ◽  
Shiro Uchida
Keyword(s):  
Solar Cell ◽  
Molecular Beam Epitaxy ◽  
Wafer Bonding ◽  
Room Temperature ◽  
Molecular Beam ◽  
Short Circuit ◽  
Short Circuit Current ◽  
Short Circuit Current Density ◽  
Device Structure ◽  
Junction Solar Cell

ABSTRACTWe studied the InGaP/GaAs//InGaAsP/InGaAs four-junction solar cells grown by molecular beam epitaxy (MBE), which were fabricated by the novel wafer bonding. In order to reach a higher conversion efficiency at highly concentrated illumination, heat generation should be minimized. We have improved the device structure to reduce the thermal and electrical resistances. Especially, the bond resistance was reduced to be the lowest value of 2.5 × 10-5 Ohm cm2 ever reported for a GaAs/InP wafer bond, which was obtained by the specific combination of p+-GaAs/n-InP bonding and by using room-temperature wafer bonding. Furthermore, in order to increase the short circuit current density (Jsc) of 4-junction solar cell, we have developed the quality of InGaAsP material by increasing the growth temperature from 490 °C to 510 °C, which leads to a current matching. In a result, an efficiency of 42 % at 230 suns of the four-junction solar cell fabricated by room-temperature wafer bonding was achieved.

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