A catalyst for manufacturing carbon substances, such as carbon nanotube that has a diameter of 1000 nm or less, the catalyst containing at least iron, cobalt or nickel of a first element group and tin or indium of a second element group. Only a final layer of the superlattice layer closest to the active region is doped with silicon, and the silicon doping concentration of the final layer is higher than that of the n-type contact layer. The connecting element further includes a support portion between the first and second anchor engaging end portions.