Scientific and technological complex for development and production of microwave devices based on silicon (Si), gallium arsenide (GaAs), indium phosphide (InP) and trinitrides (GaN, GaAlN, GaInN)

Technological complex has been created at the RI "Orion", which efficiently operates and provides a means of speedy manufacturing of silicon and gallium arsenide microwave diodes, and microwave modules based on these diodes, ranging from chemical processing of silicon and GaAs wafers up to complex tests of end products. Production and technological base of the enterprise allows us to make high quality active and passive microwave devices, modules and components, as well as multifunctional devices based on them, in the aggregate it is component framework for building electronic equipment of millimeter range of wavelengths (8-, 5-, 3 - and 2-mm).

At the RI "Orion" since 1970 and up to now silicon and gallium arsenide active and passive elements in the millimeter range (Si IMPATT packaged silicon switching diodes, varicaps, silicon distributed pin diodes, GaAs Gunn diodes) and microwave devices based on them have been developing. During this period the leading specialists of the Institute "Orion" have solved fundamental questions of diode construction upgrading and issue of impedance transformation of the diodes as well as a parameter series of diodes and a wide range of microwave devices based on them are made and industrial production are organized.

When developing basic technologies a comprehensive investigation and optimization of physical and technological fundamentals of production of silicon and gallium arsenide microwave diodes are carried out to ensure high power and reliable characteristics as well as to start effective production in market economy conditions.

Development is carried out in the following areas:

    • Optimization of doping profile and mesa configuration refining. Work in this direction is performed by method of mathematical and technological-engineering modeling. On the basis of local-field model and algorithms, developed in the RI "Orion", it was made a simulation of IMPATT-diode of p+-p-n-n+ and p+-n-n+ type in 2, 4, 5 and 8 mm wavelength ranges in continuous mode. Application packages of information with the diodes impedance characteristics for different modes of operation, as well as the conditions for maximum power and efficiency at specified thermal conditions of the active region are developed. The data are used to design diodes on which to make microwave devices.
    • Creation and comprehensive study of high-stable contact systems to silicon and gallium arsenide mesa structures. The development has been aimed at creating contact systems which provide minimal contact electrical and thermal resistance, stable during long-term operation (at temperature of 200–250°С) and are compatible with technological processes of manufacture of mesa structure and diode assembly. Multilayer contact system with barrier layer on Рt, Pd and borides of refractory metals (TiВ2, ZrВ2). were investigated using modern methods of electron microscopy, ion and Auger spectroscopy. A feature of the interaction of contact systems with silicon layers and its thermal stability in the temperature range 300–800°С. is defined. On the basis of comprehensive research the most promising contact systems based on Рd, Pt, TiВ2, ZrВ2, that are currently used in the production of silicon and gallium arsenide microwave diodes, made in the Research Institute "Orion".
    • Complex physical and chemical studies of forming silicon and gallium arsenide mesa structures. There are studied mechanical stresses and defects of microstructures occurred in active layers of a diode along the process route when forming epitaxial p-, n-layers, diffused of the p+-layer, contact systems, integral heat sink when forming mesa structure. Conditions of technological process for technological routes of mesa structure manufacturing are optimized. Quality criteria for mesa structure is defined, control methods are developed and implemented in production. Production cycle ensures the creation of mesa structures on integrated heat sink with diameters from 15 to 300 microns. Typical values of resistivity at the border of the contact systems with silicon, gallium arsenide and adhesion strength are 2–4×10-6 Ohm×сm2 и 350-400 kg/cm2 respectively.

    • Determination of thermal stability of contacts, mesa structures and reliability of the diodes. It has been investigated the thermal stability of the contacts when the exposure time is characteristic of technological operation in the temperature range 300-450°С, and duration of exposure in the temperature range 250-300°C, simulating the operation of devices. There is obtained information concerning the processes occurring at metal-semiconductor interface at elevated temperatures as well the interaction between the layers of the contact system when performing technological operations.
    • Based on these data, the critical points in the technological routes of manufacturing mesa structures, assembly, testing and operation of diodes are determined. These results are used to develop the technological routes of manufacturing chips, microwave diodes with defined electrical and reliability characteristics.

    • Optimization of assembling operation of microwave diodes into packages and microwave IC.
    • The thermal-mechanical effects on electro-physical and thermal characteristics of mesa structures are studied. The lower boundary of the temperature and pressure of micro welding instruments that do not cause micro - and macro defects has been determined. To assess the quality of micro welded compounds it is developed and used micromechanical methods of control.

      It has been developed the technological process of assembling silicon and gallium arsenide diodes in metal dielectric packages with dielectric sleeves of external diameter from 0.4 to 1.9 mm as well as diode assembling with the use of miniature quartz supports. There is also developed the technology of assembling elements of microwave IC in the form of chips of oscillating-amplifying modules. The developed technology of micro assembling operations including the quality control methods of technology processes provides a high level of diode reliability.

    • Organization of flexible manufacture of silicon microwave diodes and microwave modules based on them. Taking into account the real demand and timing of orders it was made the modernization of technological lines of Lada type for chemical processing of semiconductor wafers and metal etching (Fig. 1). Electronics 125 line is equipped with installations of combining and exposure 2104-01, ЭМ576 (Fig. 2), sputtering equipment with oil-free pumping means (Fig. 3), precision heat treatment and diffusion with furnaces of type СДОМ, Censor (Fig. 4), the micro galvanic line on the basis of units Lada (Fig. 5) focused on reducing energy consumption of technological processes along with addition of production line equipment, providing a high degree of autonomy and production mobility. There are designed and manufactured industrial equipment for assembling diodes in the miniature packages of metal ruby, metal and quartz (Fig. 6), equipment and tooling for forming thin silicon membranes and to run the process with them on the diode manufacturing technological routes. There are developed benches of controlling parameters of the diodes assembled in metal-dielectric case (Fig. 7), which ensure high quality and reliability of the components created on the basis of silicon and gallium arsenide microwave diodes.

    Fig. 1. The technological line for chemical treatment and etching of semiconductor wafers on the basis of Lada installation, fragments.

    Fig. 2. The technological line of photolithography "Electronics 125" equipped with installations of combining and exposure 2104-01, fragments.

    Fig. 3. The technological line for multilayer contact deposition on the basis of upgraded sputtering systems with oil-free pumping means of УРМ3.263.060 type, fragments.

    Fig. 4. The technological line of precision heat treatment (diffusion furnace СДО-125/3-12.0), fragments.

    Fig. 5. The technological line of micro galvanic processing on the basis of Lada installations, fragments.

    Fig. 6. The technological assembly line of silicon microwave diodes in metal-dielectric packages, fragments.

    Fig. 7. The technological line of thermo-electro training of microwave diodes, fragments.

Currently, at the RI "Orion" the technological complex has been formed that provides a means of speedy manufacturing of silicon and gallium arsenide microwave diodes, and microwave modules based on these diodes, ranging from chemical processing of silicon and GaAs wafers up to complex tests of the end products.

In technological departments of the Institute "Orion" it has been created CAD system of documentation for design and technology of microwave diodes, photo masks, elements of microwave integrated circuits and microwave devices. Using this system, it has been developing design and technological documentation for all types of silicon and gallium arsenide microwave diodes, elements of microwave IC and microwave modules for different purposes.