2-83 beam lead pin diode technical data features ? high breakdown voltage 120 v typical ? low capacitance 0.017 pf typical ? low resistance 4.7 w typical ? rugged construction 4 grams minimum lead pull ? nitride passivated description the HPND-4005 planar beam lead pin diode is constructed to offer exceptional lead strength while achieving excellent electrical performance at high frequencies. high beam strength offers users superior assembly yield, while extremely low capacitance allows high isolation to be realized. nitride passivation and polyimide coating provide reliable device protection. applications the HPND-4005 beam lead pin diode is designed for use in stripline or microstrip circuits. applications include switching, attenuating, phase shifting, limiting, and modulating at microwave frequencies. the outline 21 HPND-4005 maximum ratings operating temperature ................................................ -65 c to +175 c storage temperature .................................................... -65 c to +200 c power dissipation at t case = 25 c ........................................... 250 mw (derate linearly to zero at 175 c.) minimum lead strength ............................... 4 grams pull on either lead diode mounting temperature ............................. 220 c for 10 sec. max. extremely low capacitance of the HPND-4005 makes it ideal for circuits requiring high isolation in a series diode configuration. 130 (5.1) 110 (4.3) 130 (5.1) 110 (4.3) gold leads cathode s 1 o 2 /si 3 n 4 passivation 110 (4.3) 80 (3.1) silicon glass 25 min (1.0) 760 (29.9) 640 (25.2) 220 (8.7) 180 (7.1) dimensions in m (1/1000 inch) .4 (10) .3 (7) 320 (12.6) 280 (11.0) 220 (8.7) 180 (7.1) 60 (2.4) 30 (1.2) 5965-8877e
2-84 electrical specifications at t a = 25 c breakdown series forward reverse minority carrier voltage resistance capacitance voltage current lifetime part v br (v) r s ( w ) [2] c t (pf) [1,2] v f (v) i r (na) t (ns) [2] number hpnd- min. typ. typ. max. typ. max. max. max. min. typ. 4005 100 120 4.7 6.5 0.017 0.02 1.0 100 50 100 test i r = 10 ma i f = 20 ma v r = 10 v i f = 20 ma v r = 30 v i f = 10 ma conditions i f = 100 mhz f = 10 ghz i r = 6 ma notes: 1. total capacitance calculated from measured isolation value in a series configuration. 2. test performed on packaged samples. typical parameters i f ?forward bias current (ma) figure 2. typical rf resistance vs. forward bias current. 10,000 1000 100 10 1 rf resistance (ohms) 0.01 0.1 1 10 100 frequency (ghz) figure 3. typical isolation and insertion loss in the series configuration (z o = 50 ). 40 30 20 10 0 1 isolation (db) insertion loss (db) 11018 isolation at: ?0v ?0v insertion loss at: 10 ma 20 ma 50 ma 100 10 1 0.1 0.01 0.25 0.50 0.75 1.00 1.25 i f ?forward current (ma) v f ?forward voltage (v) figure 1. typical forward conduction characteristics. 0.08 0.06 0.04 0.02 0 0102030 capacitance (pf) reverse voltage (v) figure 4. typical capacitance at 10ghz vs. reverse bias.
2-85 bonding and handling procedures for beam lead diodes 1. storage under normal circumstances, storage of beam lead diodes in hp supplied waffle/gel packs is sufficient. in particularly dusty or chemically hazardous environ- ments, storage in an inert atmo- sphere desiccator is advised. 2. handling in order to avoid damage to beam lead devices, particular care must be exercised during inspection, testing, and assembly. although the beam lead diode is designed to have exceptional lead strength, its small size and delicate nature requires that special handling techniques be observed so that the devices will not be mechani- cally or electrically damaged. a vacuum pickup is recommended for picking up beam lead devices, particularly larger ones, e.g., quads. care must be exercised to assure that the vacuum opening of the needle is sufficiently small to avoid passage of the device through the opening. a #27 tip is recommended for picking up single beam lead devices. a 20x magnification is needed for precise positioning of the tip on the device. where a vacuum pickup is not used, a sharpened wooden q-tip dipped in isopropyl alcohol is very commonly used to handle beam lead devices. 3. cleaning for organic contamination use a warm rinse of trichloroethane, or its locally approved equivalent, followed by a cold rinse in ac- etone and methanol. dry under infrared heat lamp for 5C10 minutes on clean filter paper. freon degreaser, or its locally approved equivalent, may replace trichloroethane for light organic contamination. ? ultrasonic cleaning is not recommended. ? acid solvents should not be used. 4. bonding thermocompression: see application note 979 the han- dling and bonding of beam lead devices made easy. this method is good for hard substrates only. wobble: this method picks up the device, places it on the substrate and forms a thermo- compression bond all in one operation. this is described in the latest version of mil-std-883, method 2017, and is intended for hard substrates only. resistance welding or parallel-gap welding: to make welding on soft substrates easier, a low pressure welding head is recommended. suitable equip- ment is available from hughes, industrial products division in carlsbad, ca. epoxy: with solvent free, low resistivity epoxies (available from ablestik and improvements in dispensing equipment, the quality of epoxy bonds is sufficient for many applications. 5. lead stress in the process of bonding a beam lead diode, a certain amount of bugging occurs. the term bugging refers to the chip lifting away from the substrate during the bonding process due to the deformation of the beam by the bonding tool. this effect is beneficial as it provides stress relief for the diode during thermal cycling of the substrate. the coefficient of expansion of some substrate materials, specifically soft substrates, is such that some bugging is essential if the circuit is to be operated over wide tempera- ture extremes. thick metal clad ground planes restrict the thermal expansion of the dielectric substrates in the x-y axis. the expansion of the dielec- tric will then be mainly in the z axis, which does not affect the beam lead device. an alternate solution to the problem of dielec- tric ground plane expansion is to heat the substrate to the maxi- mum required operating tempera- ture during the beam lead attach- ment. thus, the substrate is at maximum expansion when the device is bonded. subsequent cooling of the substrate will cause bugging, similar to bugging in thermocompression bonding or epoxy bonding. other methods of bugging are preforming the leads during assembly or prestressing the substrate.
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