We have fabricated semiconducting beta-FeSi2 bulks without doping and with Mn and Co doping by using a pulse electric current sintering (PECS) method, and explored the possibility of a direct bonding of n-type and p-type beta-FeSi2 bulks to form a p-n junction structure. P-type Mn-doped and n-type Co-doped beta-FeSi2 bulks were obtained by an annealing process at 800-850 degreesC for 100 h. The PECS was applied to bond the n-type and p-type bulks together for forming a p -n junction structure. We confirmed that the bonding was processed without any change in the beta-FeSi2 phase and was strongly joined with each other. Although we could not obtain the electrical characteristics of the p-n junction, Seebeck coefficients for n-type and p-type beta-FeSi2 in the bonded sample were determined to be -356 and 778 muV/K, respectively. We propose that these results should lead to an expanded use of the sintered beta-FeSi2 bulks in thermoelectric devices. (C) 2004 Elsevier B.V. All rights reserved.