A diamond scanning element, especially for imaging application, and a method for its fabrication

A diamond scanning element for an imaging application, the diamond scanning element comprising:

• a support;
• and
• a pillar extending from the support,
• wherein the pillar has a longitudinal axis and the pillar comprises a tip with a tapered lateral section with a constantly increasing curvature,
• wherein the tip includes a sensor element, which is a defect, and
• wherein the tip has a flat end facet extending toward the axis with a gradient of less than 10%.

A method for fabricating a diamond scanning element comprising a support and a pillar extending from the support, the method comprising:

• providing a diamond material;
• depositing a resist on the diamond material;
• forming an etch mask on the diamond material;
• and
• etching,
• wherein the etching involves using a first chemical compound that primarily attacks the diamond material and thus forms a tapered conical pillar of diamond, and
• wherein the etching uses a second chemical compound, that primarily attacks the etch mask, that is added to the first chemical compound,
• wherein the etching involves first and second etching steps,
• wherein in the first etching step the first chemical compound forms the tapered conical pillar of diamond with taper angle of this section is less than 12 degrees, and wherein, simultaneously, the etch mask is eroded at an edge to form a trapezoidal cross section,
• wherein in the second etching step the etch chemistry is modified by adding the second chemical compound that etches the etch mask such that an angle of a resulting diamond sidewall is changed,
• wherein the first chemical compound is O2 and the second chemical compound is CF4, and
• wherein multiple CF4:O2 ratios are used sequentially to obtain a curved surface profile.