A short review of thin-film write heads, all formed on magnetically flat substrates, is given, and properties of the several types are discussed. A novel structure is proposed to avoid many disadvantages of the former heads. It is formed on a magnetically grooved but physically planar substrate. Measured and calculated characteristics are given for this new configuration for which the name "groove structure" is proposed. The groove structure turns out to be more effective than a magnetically flat substrate. A thin-film write head on the groove structure has 30 (60 as stagger) tracks per quarter inch and a common biasing line effectively to reduce the signal write current.