MIL-PRF-38535K
APPENDIX H
c. Bipolar parameters. Care should be taken in the manner and sequence in which all breakdown voltage and current
measurements are taken so as to not permanently alter the device for other measurements.
(1) Sheet resistance: Structures should be included which can be used to measure sheet resistance of all doped
regions (e.g., emitter, buried collector.)
(2) Schottky diode parameters: The following measurements should be made on Schottky diodes representative of
the size used in the technology:
(a) Reverse leakage: The reverse leakage current (IR) should be measured at a specified reverse voltage.
(b) Reverse breakdown: The reverse breakdown voltage (BV) should be measured at a specified current.
(c) Forward voltage: The forward turn-on voltage (Vf) should be measured at a specified current.
(3) Bipolar transistor parameters: The following measurements should be made on bipolar transistors representative
of the size and type used in the technology. The types should include NPN, Schottky clamped NPN, vertical
PNP, substrate PNP, and lateral PNP transistors as applicable.
(a) Transistor gain: The common emitter dc current gain (Hfe) should be measured on representative
transistors over three decades of collector current, the highest point of which is at the maximum rated
current of the device.
(b) Leakage currents: The leakage currents (ICEO, ICBO, and IEBO) should be measured on representative
transistors at a specified voltage.
(c) Breakdown voltages: The breakdown voltages (BVEBO, BVCBO, and BVCEO) should be measured on
representative transistors at specified currents.
(d) Forward voltages: The forward voltages (VBEO and VBCO) should be measured on representative transistors
at the rated currents.
(e) Propagation delay: A test structure should be available in the form of a functional circuit from which
propagation delay information can be measured at room temperature.
(4) Isolation leakage: The isolation leakage current (IL) between minimum spaced adjacent transistor collectors
should be measured at a specified voltage.
d. GaAs parameters.
(1) Sheet resistance: Structures should be included which can be used to measure sheet resistance of each of the
conducting layers.
(2) Metal-insulator-metal (MIM) capacitor: Capacitor test structures should be included so that dc and rf capacitance,
leakage, and breakdown can be measured.
(3) FAT FET: A long gate length FET suitable for measurement of Schottky barrier height and ideality factor, carrier
concentration and mobility, and channel depth should be included.
(4) Isolation: A structure for use in measuring substrate isolation breakdown should be included.
(5) Ohmic contacts: An ohmic contact transmission line structure should be included so that specific contact
resistance and transfer length can be measured.
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