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449-452_konakova.p65

Semiconductor Physics, Quantum Electronics & Optoelectronics. 2002. V. 5, N 4. P. 449-452.
A universal automated complex for control and diagnostics of semiconductor devices and structures R.V. Konakova, O.E. Rengevych, A.M. Kurakin, Ya.Ya. Kudryk Institute of Semiconductor Physics, NAS Ukraine, 45 prospect Nauky, 03028 Kyiv, Ukraine Phone: 38(044) 265 6182; fax: 38(044) 265 8342; e-mail: [email protected] Abstract. We present a universal automated complex for control and diagnostics. It is in- tended to measure static, pulse and capacitance-voltage characteristics of two- and three- terminal networks, both at room temperature and in 77–1000 K temperature range. A distin- guishing feature of complex construction is the possibility for simulation of interrelation between parameters of the objects studied. The complex has been tested when studying the effect of γ- and microwave radiations on parameters of gallium arsenide SB-FETs, GaN-based HEMTs and silicon carbide SBDs.
Keywords: diagnostics of semiconductor devices, automation of measurements.
Paper received 31.07.02; accepted for publication 17.12.02.
operation speed (no more than 20 measurements per sec- ond [5]) are not optimal for their use in test rigs for ex- Present-day manufacturing of semiconductor element press check of parameters and characteristics of semi- base is characterized by a wide range of products that differ in their specifications and applications. Manufac- The domestic complexes for control and diagnostics turing dependence on rapidly varying market situation are made on the basis of industrial curve tracers. They requires new instrumentation for check and measurement make it possible to take characteristics of semiconductor to provide competitive ability. Such instrumentation devices of practically all types over wide range of cur- should be sufficiently flexible for easy integration into rents and voltages. However, their operation speed is low the existing measuring complexes, as well as possess wide and, as a result, their use is costly [6, 7]. Solution of this functional capabilities that would enable to modify com- problem lies in development of domestic multifunctional automated complexes characterized by high operation Now at research laboratories, as well as in industry, instrumentation of Western production for check and di- Here we present the results of our activity in this line agnostics is widely used [2-4]. Among the most popular taking, as an example, development and fabrication of instruments are, for instance, such as automated curve both hard- and software for a universal automated com- tracers HP 4145 and HP 4155 whose range of currents plex for control and diagnostics of semiconductor devices.
(voltages) measured is 10–12–10–1 A (10–3–102 V), the rela- This complex is a logic extension of the test rigs for check tive measurement error being no more than 0.5 %; pre- and diagnostics that have been developed and fabricated cise LCR-meters HP 4284, Genrad 1689 whose ranges of resistances, inductances and capacitances measured are 10–2–105 Ω, 10–8–105 H and 10–14–10–1 F, respec- 2. Construction and potentialities of the tively, the relative measurement error being no more than 0.2 %. At the moment these instruments meet the require- ments imposed on the facilities of such class and provide The block diagram of our complex for control and diag- high accuracy and reproducibility of the results of meas- nostics is presented in Fig. 1. The complex is made on the urements. However, their high cost and relatively low 2002, Institute of Semiconductor Physics, National Academy of Sciences of Ukraine R.V. Konakova et al.: A universal automated complex for control and .
Fig. 1. Block diagram of the complex. ADC – analog-to-digital converter, DAC – digital-to-analog converter, GPIB – generalpurpose interface bus, I/U – current-to-voltage converter, PA – programmable amplifier.
basis of IBM-compatible computer (486DX80). Its func- ties of the complex can be realized independently (or with an incomplete set of functions). This fact may consider- 1) measurements of static I-V curves for two- and three-terminal networks in the range of currents from The complex construction involves two boards built 1×10–11 to 2 A and voltages up to 50 V (two ranges: 0–10 V into computer (bus ISA), a voltmeter Â7-21À, bridge Å7- and 0–50 V), the relative measurement error being no 12, thermostat, unit to control thermostat, contact facil- ity (when the devices on a wafer are measured, this is an 2) measurements of pulse I-V curves for two- and automated probe À5). A board that is built into the com- three-terminal networks in the range of currents from puter has two 12-bit digital-to-analog converters (DACs), 1×10–4 to 2 A and voltages up to 10 V at pulse duration a current-to-voltage converter, programmable amplifier, (programmable) from 10–6 s to the case of continuous 12-bit analog-to-digital converter (ADC) and program- current, the relative current measurement error being no mable timer, as well as a general purpose interface bus (GPIB) controller board. In this configuration the GPIB 3) measurements of C-V curves in the range of controller is used only to connect a bridge Å7-12 for meas- capacitances from 10–14 to 10–7 F, the relative measure- urement of C-V curves. However, application of the GPIB controller (that is a traditional interface in various mod- 4) measurements of C-V curves and static I-V curves ern devices, of domestic, as well as overseas, production) enables to extend the complex capabilities by connect- 5) protection of sample tested against current over- One of distinguishing features of the complex is ap- 6) possibility to perform measurements for both dis- plication of standard computer interfaces for data ex- change with the peripheral facilities. To illustrate, a volt- 7) possibility to perform simulation of interrelation meter Â7-21À that is used when measuring static I-V curves between the parameters of objects studied, as well as com- of two- and three-terminal networks is served by an inter- plete automation of measurements (no operator attention face “Centronics” (printer port LPT1). The data given is required during the measurement process for devices of by a device are read from numeric printer interface in binary-decimal code, multiplexed and transmitted to com- 8) high operation speed (to illustrate, a set of eight I- puter through interface “Centronics”. Control over the V curves – 255 points for each – is measured for 5 ms, i.e., automated probe À5 is also exerted through the printer port (LPT1). At a later time we plan to completely rule The complex was designed as a multifunctional facil- out the boards built into computer. Their functions will ity of open architecture. Such an approach enabled us to be realized on the basis of microcontrollers connected to make a flexibly adjustable system involving test rigs that computer through serial port. Such modification will complemented each other. They had a common compu- made the complex still more universal and independent ter and common software. Each of functional potentiali- R.V. Konakova et al.: A universal automated complex for control and .
of computer configuration and presence (or absence) of The operation parameters of HEMTs found from the experimental I-V curves (saturation current, transconduc- Setting of a required temperature value in the thermo- tance, cutoff voltage) and characteristic resistance dem- stat can be made by a signal from computer, as well as onstrated high reproducibility. Shown in Fig. 3 are typi- manually. Control from computer is made by applying a cal C-V curves for SiC-based diodes (a) and typical tem- digital or analog signal (applying a corresponding volt- perature dependence of I-V curves for SiC-based diode.
age from DAC). When hand-operating, control is exert- ing by setting a code that is proportional to temperature.
Processes of temperature establishment are regulated by U = 0 V
the microcontroller in the thermostat control unit. Feed- G
back with computer is made only when a ready signal comes from the thermostat. The temperature setting er- ror in the 77–1000 K range is ± 0.5 K. Stability of tem- perature maintenance is 0.1 K; this is twice as good as that provided by the technique proposed in [12].
Application of a miniature Schottky-barrier (SB) di- I S-
ode as a temperature sensor demonstrating linear tem- perature dependence of voltage (at a constant value of diode current) over the whole operating range made it U = 4 V
possible to rule out a compensation thermocouple. (One G
of its junctions had to be at a constant temperature, or U
this temperature had to be uninterruptedly monitored – say, with a semiconductor sensor, as it was made in [13].) Fig. 2. I-V curves for a GaN-based transistor taken in the pulse To provide the most complete use of complex potenti- (full curve) and static (dashed curve) modes.
alities, we have developed common software. This made it possible not only to exert efficient control over the sys- tem, but also to perform simulation of interrelation be- a
tween parameters. From the results of measurements the following characteristics are calculated: saturation cur- rent, transconductance, cutoff voltage, channel and con- tact resistances – for field-effect transistors (FETs); Schottky barrier height, ideality factor, saturation cur- 2 ,C
rent and series resistance – for diodes; temperature de- pendence of parameters and their distribution over wa- fer. When studying the effect of external factors (radia- tion, microwave field, thermal annealing, ultrasound, etc.), the complex enables one to obtain the database for U , V
the above parameters and perform analysis of their depend- ence on these factors. Software (common for the whole com- plex) makes it possible to perform simulation of interrela- tions between the parameters of the objects studied.
The complex has been tested when studying the effect of γ- and microwave radiation on the parameters of low- noise gallium arsenide SB-FETs and test pieces of FETs, as well as high electron mobility transistors (HEMTs) based on GaAs [14] and GaN. The device characteristics were measured in the pulse mode. This made it possible I, A
to practically completely exclude the effect of device struc- ture heating. Shown in Fig. 2 are I-V curves taken in the pulse (full curve) and static (dashed curve) modes for the same transistor. One can see that at high drain-source voltages a portion of I-V curve with negative differential resistance is observed in the static mode. This results from b
structure overheating with current. It should be noted that such pattern is observed even with allowance made for the fact that time of measurement for the whole set of I-V curves (when the sample studied under load) is from 1 to U , V
2 s, depending on the intervals between consecutive gate- Fig. 3. Typical C-V curves for SiC-based diodes (a) and typical source and drain-source voltage values.
temperature dependence of I-V curves for SiC-based diodes (b).
R.V. Konakova et al.: A universal automated complex for control and .
5. Advanced Test Equipment // www.atecorp.com 6. V.N. Petrov, M.N. Petrov, An automated meter of static pa- rameters of semiconductor devices // Izmeritel’naya Tekhnika We have developed and tested a universal automated com- No 12, pp. 49-52 (1996) (in Russian).
plex for control and diagnostics. It enables to measure 7. V.T. Kremen, An automated meter of parameters of semicon- static, pulse, C-V curves and temperature characteristics ductor devices // Izmeritel’naya Tekhnika No 9, pp. 31-34 of two- and three-terminal networks, as well as process the results obtained (performing calculation operations 8. R.V. Konakova, E.A. Soloviev, O.E. Rengevich, Facilities and techniques for diagnostics of microwave diodes and tran- during measurements), present and save information in a sistors, in 7th Intern. Crimean Conf. “Microwave & Telecom- munication Technology”, Conf. Proc., Sevastopol, Weber Co., Such complex features, as multifunctionality, univer- sality, small size, high operation speed, possibility to 9. I.Yu. Il’in, R.V. Konakova, O.E. Rengevich, E.A. Soloviev, A measuring module and software for test rig to check FET extend and modify its functional potentialities, enable parameters // Izvestiya Vuzov. Elektronika No 4, pp. 101-104 one to use this complex as part of various plants for con- trol and diagnostics, both for researches and in industry, 10. O.E. Rengevich, Effect of g-radiation and microwave radia- to check device parameters and reject potentially unreli- tion on the SB-FET parameters, Author’s Abstract of the able devices at the output inspection stage.
Candidate of Tekhnical Sci. Thesis, Kiev, Institute of Semi- conductor Physics of the National Academy of Sciences of 11. N.A. Charykov, M.L. Belousov, M.V. Perevozchikov, Yu.V.
Oreshnikov, V.N. Danilin, T.A. Zhukova, A programmable computer complex for determination of contact resistance to 1. R.V. Konakova, Yu.A. Tkhorik, V.I. Faynberg, E.A. Soloviev, gallium nitride and related materials, in Abstracts of the All- F. Štofanik, Diagnostics of semiconductor devices from their Russia Conf. “Gallium, indium and aluminum nitrides – struc- electric, photoelectric and pulse characteristics using the com- tures and devices”, Moscow, 1-2 November 2001, p. 17 (in plex “Capron” // Optoelektronika i Poluprovodnikovaya Tekhnika No 18, pp. 35-46. (1990) (in Russian).
12. F. Draghici, F. Mitu, G. Dilimot, I. Enache, Method to in- 2. L.S. Yu, D. Qiao, L. Jia, S.S.Lau, Y. Qi, K.M. Lau, Study of crease the thermal stability of the heating circuits, in CAS’98 Schottky barrier of Ni on p-GaN // Appl. Phys. Lett. 79(27), Proc. (1998 Int. Semicond. Conf., Sinaia, Romania), 2, pp.
3. Q. Chen, J.W. Yang, M. Blasingame, C. Faber, A.T. Ping, I.
13. V.T. Kremen, A wide-range temperature regulating device Adesida, Microwave electronics device applications of AlGaN/ with automatic setting for regulated object // Pribory i GaN heterostructures // Mater. Sci. & Eng. B59, pp. 395-400 Tekhnika Eksperimenta No 5, pp. 158–160 (1998) (in Rus- 4. C.A. Dimitriadis, Th. Karakostas, S. Logothetidis, G.
14. O.E. Rengevich, Radiation effects in HEMTs // Pis’ma v ZhTF Kamarinos, J. Brini, G. Nouet, Contacts of titanium nitride 25(25), pp. 55-58 (1999) (in Russian).
to n- and p-type gallium nitride films // Solid-St. Electron. 43,

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