Main Sector of relevance\IRC classification 5. Electronics, IT and Telecommunication

5.37 Development of radiotechnological methods for production of powerful quick-acting semiconductor devices

Developers’ contact information

SSPA “The Scientific and Practical Materials Research Center of the National Academy of Sciences of Belarus”
19, P. Brovka Str., 220072 Minsk

Summary

The physical bases and practical methods for use of penetrating rays in the technology of power semiconductors, including powerful silicon diodes, insulated-gate bipolar transistors, have been developed. The high efficiency of radiotechnological application for speeding up of bipolar devices, exception of gold or platinum diffusion process, quality improvement, reduction of costs and yield increase have been shown. The radiotechnological methods developed in State Association “Scientific and Practical Materials Research Center of the National Academy of Sciences of Belarus” are used in the electronic industry of the Republic of Belarus.

Description

The burning issue of semiconducting instrumentation is quality enhancement and increase in yield ratio of semiconductor devices, reduction of their production costs and guarantee of high competitive ability. To a large extent, the problem may be solved by introducing semiconductor devices of radiotechnological methods which are based on use of penetrating rays. In semiconductor crystals with р-n passages, instead of chemical gold or platinum impurities, specified types of radiation defects leading to fundamental improvement of instrument characteristics are strictly dosed by penetrating radiation (high-speed electrons, gamma quantum).
High-power diodes, insulated-gate bipolar transistors (IGBT) that are actively used in different industrial and home devices (in powerful switching equipments, power supplies, in-car electronics and other spheres) require enhancement of their operating speed and minimization of commutative energy losses.The dependence of dynamic and static parameters of powerful p-n diode structures on electron fluence with energy E = 4 MeV has been defined. This dependence is used for adjustment of high-power diodes parameters with the help of radiotechnological technologies. In particular, the operating speed of powerful silicon diodes has increased 13÷15-fold together with retention of static parameters within the technical conditions limits.
It has been found out that together with increase in electron irradiation, IGBT operating speed increases as well (the turnoff time reduces 5-fold) with retention of static parameters within the specification requirements limits. The postradiational bakeout leads to stabilization of all transistor parameters.

Technology type

• Process

Technical advantages and economic benefits

Earlier on, increase in operating speed of semiconductor devices was achieved by injection of gold or platinum impurities into their volume that formed recombination centers reducing the lifetime of minority charge carriers. But such a manufacturing method has material weaknesses related to uneven distribution of abovementioned impurities in silicium volume due to gettering them with crystal defects. It reduces the performance reproducibility and increases dispersion in accordance with speed of instruments, this is most typical of high-power diodes with significant р-n interfaces area.
The main advantages of use of radiation methods against conventionally used diffusion methods consist in the following:

• They permit to accurately dispense the concentration of radiation defects (RD) being the recombination centers;
• To add RD extremely uniformly all over the semiconductor structure area that eventually increase the apparatus percentage yield;
• To add to semiconductor structures various types of RD, concentrations of which one against another may be changed with the help of additional thermal processing, achieving at the same time necessary combinations of dynamic and static parameters.

Technology differentiation and uniqueness

The radiotechnological methods for production of powerful quick-operating semiconductor devices may be used in electronic industry. The amount of financing: under agreement.

Context in which technology was identified

Unitary Enterprise “Transistor Plant”, Production and Research Corporation “Integral”.

Technological keywords

Radiotechnology, powerful quick-operating semiconductor devices, electron irradiation.

Development Stage

• Results of demonstration test available

Intellectual property rights

• Patent pending
• Specific Patent Information:
  Patent RB No 11307 “Method of producing quick-operating high-voltage diodes”/ F.P. Korshunov, I.G. Marchenko, N.E. Zhdanovich, V.I. Kulgachev. Application No 20070642, May 28, 2007.

Range of applications

The radiotechnological methods for production of powerful quick-operating semiconductor devices may be used in electronic industry.

Classifier Used at the EU Innovation Relay Centres

• Electronics, IT and Telecommunication

Preferable Regions

• Europe
• Asia

Practical experience

The radiotechnological methods have been successfully developed over the period of more than 30 years in the laboratory for radioactive effects of State Association “Scientific and Practical Materials Research Center of the National Academy of Sciences of Belarus”; there are necessary irradiating installations (two linear electron accelerators and a gamma-ray source), measuring equipment and highly experienced scientific personnel.

Environmental impact

None.

Type of collaboration sought

• R&D contract

Terms and restrictions

None.

Available technical assistance

• Documentation