ISSN 1063-7397, Russian Microelectronics, 2016, Vol. 45, No. 7, pp. 469–473. © Pleiades Publishing, Ltd., 2016.
Original Russian Text © F.I. Grigoriev, A.B. Aleksandrova, V.A. Gafurov, 2015, published in Izvestiya Vysshikh Uchebnykh Zavedenii, Elektronika, 2015, Vol. 20, No. 3, pp. 239–245.
A Method for Calculating the Thermal Characteristics
of Silicon TVS-Diodes in the Pulse Mode
F. I. Grigoriev
, A. B. Aleksandrova
*, and V. A. Gafurov
Moscow Institute of Electronics and Mathematics, National Research University Higher School of Economics, Moscow, 115054 Russia
Dukhov All-Russian Research Institute of Automatics, Moscow, 101000 Russia
Received October 10, 2014
Abstract—The dependence of the thermal characteristics of TVS-diodes during the passage of the pulse over-
load has been studied. The time dependences of the pulse voltage limitation and current are analyzed. Based
on the analysis of the dependences, the thermal characteristics of the TVS-diode are calculated. It is shown
that the parameters of the TVS-diodes deteriorate on reaching a current density of 160–300 A/cm
ical temperature of 250–300°С. The dependences of the thermal resistance and critical temperature of the
TVS-diodes on the current density and the pulse duration are presented.
Keywords: TVS-diode, current pulse, critical temperature, heat resistance, current density, transient heat
resistance, avalanche breakdown, thermal breakdown, pulse duration
A thermal breakdown is the basic reason for cata-
strophic failures of semiconductor devices. When
passing through the pulse overload the thermal energy
is released in the localized region of the p–n-junction
on the low-doped side and the temperature becomes
critical. At this temperature the local resistance drops
and the local current density rises. As a result, the sil-
icon melts and, as a consequence, the р–n-junction is
The estimate of thermal limitations in the pulse
operation mode of avalanche diodes showed that,
when the duration of the operating pulse is 300 ns and
the current amplitude is up to 15 A, the overheating of
the р–n-junction relative to the environment is 270–
430°С . The boundary superheating temperature of
the p–n-junction is 350°С (at a higher temperature the
avalanche diodes deteriorate).
The KD208 rectifying diode crystals were studied
under the action of pulses with a duration of 5 ms .
The dependences of the direct resistance of the diodes
on the number of pulses and the temperature of the
crystal on the duration are given there. The depen-
dence of the crystal temperature on the number of
sequentially applied pulses at different pulse ampli-
tudes is also estimated.
One of the widespread small-sized means of pro-
tection of semiconductor devices against pulse over-
loads are silicon TVS-diodes.
Such a TVS-diode should ensure long-term opera-
tion, scattering high-power parasitic pulses.
The basic pulse parameters of the TVS-diode are
the pulse limitation voltage U
, pulse current
, inverse pulse power Р
, inverse pulse energy
, and internal thermal resistance R
The purpose of the present work is to study the
dependences of the thermal resistance and critical
temperature of a TVS-diode during the passage of the
SAMPLES AND METHODS
OF THEIR INVESTIGATION
The TVS-diode crystal consists of four plates, con-
nected in series by the soldering method. The two
outer plates (n
) ensure the ohmic contact and the two
inner plates are formed by two back-to-back p–n-
junctions (Fig. 1а). The reverse voltage of the studied
TVS-diode is 150 V.
The volt–ampere characteristic of the symmetrical
TVS-diodes is shown in Fig. 1b. The threshold voltage
of the TVS-diodes is lower than the limitation
lim pulse max
, ensuring their automatic discon-
nection from the direct-current circuit upon the pas-
sage of the pulse overload .
To study the response of the TVS-diodes to the
action of a single current pulse (SCP), the experimen-
tal test bench, which generates exponential-shape cur-
rent pulses, is designed (Fig. 2а).