Charged particle beam apparatus and method of forming electrodes having narrow gap therebetween by using the same

A method of forming electrodes having a narrow gap therebetween comprising the steps of:

• providing a sample the surface of which is constituted by an insulating member, two electrodes made of a conductive thin film being provided on the insulating member, and a groove being provided between the two electrodes;
• bringing the probers into contact with the two electrodes;
• setting a forming region of a conductive thin film to ride over the groove between the two electrodes;
• forming the conductive thin film by scanning the charged particle beam while blowing the gas to the forming region of the conductive thin film;
• applying the constant voltage to between the two electrodes;
• measuring a current flowing between the two electrodes;
• detecting that a current value becomes larger than a predetermined value;
• and
• finishing to scan the charged particle beam to the forming region of the conductive thin film.

A method of forming electrodes having a narrow gap therebetween comprising the steps of:

• forming a pair of electrodes opposed to each other by providing an insulating gap on a sample;
• and
• forming a conductive film to narrow the gap between the electrodes while applying a voltage between the electrodes and measuring a current flowing between the electrodes;
• finishing to form the conductive film when the current flowing between the electrodes becomes a predetermined value.

A charged particle beam apparatus comprising:

• a charged particle source;
• a focusing lens system for focusing a charged particle beam drawn out from the charged particle source;
• a blanking electrode for making the focused charged electron beam ON/OFF on a sample;
• a deflection electrode for deflecting to scan the focused charged particle beam;
• a movable sample stage mounted with the sample irradiated with the focused charged particle beam;
• a gas gun for locally blowing a gas to a position of irradiating the focused charged particle beam on a surface of the sample;
• a secondary charged particle detector for detecting a secondary charged particle generated by irradiating the focused charged particle beam to the sample;
• two pieces of probers brought into contact with two points on the surface of the sample;
• a voltage source for applying a constant voltage between the two points with which the probers are brought into contact;
• an ammeter for measuring a current flowing between the two points;
• and
• control means for forming, a conductive film between the two points to narrow a gap therebetween by operating the deflection electrode and the gas gun, monitoring the current flowing between the two points, and making the focused charged particle beam irradiated to the surface of the sample off by the blanking electrode when the current becomes a predetermined value.