The current-voltage (I-V) characteristics of large area (5 mm(2)) 4H-SiC pn diodes fabricated by liquid phase epitaxy (LPE) were studied up to 2 kA/cm(2) in the temperature range from 20 to 300 degreesC. At 200 A/cM(2) and room temperature, the forward voltage drop (V-F) was measured to be 3.7 V. The specific on-state resistance (R-on) was found to be (2.3-3.4) mOhm(.)cm(2). The VF showed a negative temperature coefficient in the investigated region. The long-term stability testing of the pn diodes during 100 hr at forward current density of 200 A/cm(2) was performed. The VF increased by 0.2 V with time. Deep traps were investigated before and after long-term testing. A deep trap with thermal activation energy of E-C-1.43+/-0.03 eV was detected after diode operation during 20 hr at 200 A/cm(2). It is speculated that this deep trap determines the degradation of electrical characteristics.