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Shielded spin-valve tape heads with permanent magnet stabilization are described. Final MR of 3.5% is shown on heads with trackwidths of 5 and 9 [[micro]meter], and sensor heights of 0.5, 1.0 and 1.5 [[micro]meter]. Heads are characterized on 1/2[inch] DLT-IV tape up to 180 kfci. For isolated transitions the heads show a [PW.sub.50] of 0.8 [[micro]meter] (pulse broadening due to partial head saturation) and a baseline shift [approximately]10% that can be positive or negative, and is related with shield remanence and transfer curve hysteresis. At 120 kfci, head output for a sense current of 3 to 4 mA is [approximately] 1 [mV.sub.pp] (up to 30% of the output at 30 kfci). At high linear densities, signal loss is 0.24 dB/kfci for a 0.35 [[micro]meter] shield-to-shield spacing ([D.sub.50] of 80[approximately]100 kfci). At low linear densities the head is partially saturated, and above 60 kfci harmonic distortion is lower than -20 dB. Index Terms - magnetic recording/reading heads, magnetoresistive materials and devices, spin valve heads, tape recording.

A new exchange material, [Mn.sub.78][Rh.sub.22], is described, requiring no post-deposition anneal to obtain the antiferromagnetic phase and leading to spin valve sensors with good corrosion resistance, thermal stability up to 225 [degrees] C, and good exchange coupling characteristics. Potentiodynamic polarization scans performed in a sodium sulfate electrolyte show that [Mn.sub.78][Rh.sub.22] films exhibit a good corrosion resistance, comparable to that of [Ni.sub.81][Fe.sub.19], [Mn.sub.80][Ir.sub.20], and [Mn.sub.50][Ni.sub.50] films but with higher corrosion potential. Spin valve structures prepared with this exchange material show an exchange coupling strength ([J.sub.ex]) of 0.19 erg/[cm.sup.2]. The blocking temperature ([T.sub.B]) of the as-deposited spin valve coupon samples is 235 [degrees] C. Unshielded sensors with trackwidths W = 4-6 [[micro]meter] and height h = 1-2 [[micro]meter] were fabricated. The sensors show well-linearized magnetoresistance (MR) transfer curves, without hysteresis or Barkhausen noise and are thermally stable under consecutive 5 h anneals in vacuum up to 225 [degrees] C. A shielded tape head device was fabricated showing a maximum output of 1.8 m[V.sub.pp]/[[micro]meter], with potential for operating at linear densities near 100 kfci, at which a 580 [Mu][V.sub.pp]/[[micro]meter] output is measured. Index Terms - Corrosion resistance, exchange layers, magnetic recording/reading heads, magnetoresistive materials and devices, spin valve heads.

A micromagnetic model was developed to study a 4-terminal, insulating spacer Dual-Stripe GMR head (DSGMR) operating in differential mode, and a 2-terminal, high resistivity conducting spacer, Dual-GMR head. Pulse shape and magnetization distributions were correlated with current biasing and non-linear effects. For two (Ni[Fe.sub.20[Angstrom]]/[Cu.sub.20[Angstrom]]).sub.10] GMR elements and a gap of 500[Angstrom], the DSGMR shows higher output than the Dual-GMR at frequencies < 400kfci but has a gap null at 570kfci. The Dual-GMR has a higher output above 400kfci, but shows no common-mode effect cancellation, characteristic from dual-stripe heads in differential mode. A single element GMR tape head was fabricated and results compared with simulation. Index Terms - Magnetoresistive heads, Magnetic Recording, Dual-Stripe Sensors, GMR heads, Micromagnetic Simulation.