An electron-emitting device having little dispersion of its electron
emission characteristic and a suppressed "fluctuation" of its electron
emission quantity is provided. The electron-emitting device includes a
substrate equipped with a first portion containing silicon oxide and a
second portion arranged abreast of the first portion and having a higher
heat conductance, and an electroconductive film including a gap therein,
the electroconductive film arranged on the substrate, wherein the first
and the second portions having a resistance higher than that of the
electroconductive film, and the gap is arranged on the first portion.