JPS63297600A - Method and device for forming needle-like body - Google Patents

Abstract

PURPOSE:To stably form a needle-like body having a small amt. of eccentricity of the axial center by immersing the tip of a material to be polished into the specific position under the surface of an electrolyte and subjecting the tip to electrolytic polishing while rotating said material. CONSTITUTION:A vertically working head 6 is lowered by driving of a motor 66 in a needle-like body forming device and a tip 1 mounted by a chuck 71 is lowered to a spindle 7 mounted thereto. The position of the liquid surface is detected by an electrolyte level detector upon arriving of the end of the tip 1 at the surface of the electrolyte 2. The tip 1 is further lowered and is stopped at the specific position under the liquid surface. The tip 1 is rotated by a revolving motor 72 in the electrolyte 2 which is kept at a prescribed temp. by a heating medium liquid 23. The cathode 4 in the electrolyte is energized from the tip 1 through a current collecting pulley 75 simultaneously therewith by which the electrolytic polishing is executed. Preferably, the rotation of the tip 1 is thereafter stopped for the specific time or at the specific current value before the attainment of the final polishing time or current value and the electrolysis is continued up to the final time or current value. The distance from the electrolyte surface to the tip 1 end is thereby uniformized.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a method and apparatus for forming a needle-shaped body used in a focused ion beam device, a scanning tunneling effect microscope, and the like.

[Summary of the invention]

In the formation of needle-shaped bodies by electrolytic polishing, the present invention enables electrolytic polishing to be performed while rotating the needle-shaped bodies after immersing the tip of the needle-shaped bodies in a specific position below the surface of an electrolytic solution. It is.

[Conventional technology]

Previously, JP-A-60-1717. Japanese Patent Publication No. 60-91529
．． A needle-shaped body (hereinafter referred to as a chip) was formed using a method such as that disclosed in Japanese Patent Application Laid-Open No. 61-32326, but as shown in FIG. 1) is held at a specific position below the surface of the electrolytic solution 2 using a tool scope 10, and a current is applied between the cathode 4 and the chin 1) using a constant current source 3 for a certain period of time using a timer 8. Then, the chip 1 was electrolytically polished.

[Problem that the invention seeks to solve]

However, as shown in FIGS. 4 and 5, in the conventional electrolytic polishing method, it is not only difficult to insert the chip 1 perpendicularly to the electrolyte surface 21, but also the chip It is almost impossible to maintain a constant distance from the tip 20 of 1. Therefore, compared to the chip shape 1) before electropolishing, the chip shape 12 after electrolytic polishing has a drawback in that the tip 20 of the chip 1 is formed at a position shifted from the chip axis.

Therefore, in order to solve such drawbacks of the conventional technology, the present invention has been developed so that the tip of the tip can be stably formed on the axis even if the relationship between the electrolyte level and the tip is not perpendicular but inclined. The aim is to do what is possible.

Means for Solving Problem c] In order to solve the above problems, the present invention provides a rotation mechanism for a polished object, an electrolyte level detection device, an electrolytic polishing current detection device, a chaffing mechanism for a polished object, and Equipped with a vertical movement mechanism,
Polishing length due to poor perpendicularity to the electrolyte surface of the object to be polished,
This is to prevent instability of the axis deviation amount.

[Effect]

When the object to be polished is attached to the needle-like object forming device configured as described above and subjected to electrolytic polishing, the distance from the electrolyte level to the tip of the needle-like object, which is the object to be polished, becomes uniform over the entire circumference. Therefore, it is possible to obtain a stable needle-like body with a small amount of axial center deviation.

〔Example〕

Embodiments of the present invention will be described below based on the drawings.

In FIGS. 1 and 2, when the polishing start button (not shown) is first pressed, the vertical operation motor 66 is driven, and the vertical operation head 6 moves downward and is attached to the chuck 71 at the tip of the spindle 74. When the tip of the tip 1 reaches the surface of the electrolyte 2 heated by the heater 22 and the heating medium 23, the position of the liquid level is confirmed by the electrolyte level detection device, and that point is set as the origin. The vertical operation head 6 continues to descend until it reaches a specific position below the liquid level, and stops at the set position. Thereafter, in response to a stop signal for vertical operation, the rotary motor 72 starts rotating, rotates the chip 1, and at the same time flows a current from the current collection pulley 75 to the chip l and between the chip l and the cathode 4 to cause electrolysis. Polish. After that, the rotation of the chip 1 is stopped for a preset time or when the current value becomes lower than the current value, and electrolytic polishing is continued.
At the final time or when the current value falls below the final value,
The electric current between the chip 1 and the cathode 4 is stopped, and the vertical motor 66 is driven to lift the chip 1 from the electrolytic solution 2, thereby completing the electrolytic polishing. Moreover, it is also possible to obtain needle-like bodies of various shapes by repeatedly performing the above operation at a plurality of positions below the surface of the electrolyte.

In the embodiments described above, even if the level of the electrolytic solution 2 and the tip 1 are not perpendicular enough, rotating the tip 1 produces the same effect as if the perpendicularity was achieved.

(Effects of the Invention) As explained above, the present invention uses a simple method of rotating an object to be polished, such as a needle, to reduce the amount of axial deviation of the tip of the needle. This has the effect of obtaining a highly accurate needle-like body.Also, by holding down the position of the electrolytic solution level and the tip of the object to be polished, it has the effect of stabilizing the shape of the needle-like body.

[Brief explanation of drawings]

FIG. 1 is a side view showing the configuration of the needle-like body forming apparatus according to the present invention, FIG. 2 is a flow chart diagram of the needle-like body forming apparatus according to the present invention, and FIG. 3 is a conventional electrolytic polishing method. FIG. 4 is an explanatory diagram of the state of chip polishing in conventional electrolytic polishing, and FIG. 5 is an explanatory diagram of chip shape in conventional electrolytic polishing. l... Chip 2... Electrolyte 3... Constant current source 4... Cathode 5... Petri dish 6... Z stage 7... Chip support 8... Timer 9... Vertical operation
10...Tool scope 1)...Chip shape before electrolytic polishing 12...Chip shape after electrolytic polishing 13...Amount of axis deviation 14.15...Polishing length 22...Heater 23
...Heating medium liquid 33...Control device 71...Chuck 72...Rotating motor 73...Rotating pulley 74...Spindle 75...Collecting pulley and above Applicant Seiko Electronics Industries, Ltd. For the invention of wood/)'7)'The shape of the tree is the shape of the tree, and the shape of the tree is the city of the device. Figure 2 (2I) of the flowchart of the device

Claims (4)

[Claims] (1) In the production of needle-like objects used in focused ion beam devices (FIBs), scanning tunneling microscopes (STM), etc., electrolytic polishing is performed while rotating the object to be polished. How the body is formed. (2) Electrolytic polishing is performed while rotating the object to be polished, and the final polishing time or a specific time before reaching the current value, or
The method for forming a needle-shaped body according to claim 1, wherein the rotation is stopped at a current value. (3) A needle-like body forming apparatus characterized by comprising a rotating mechanism for a polished object, an electrolyte level detection device, an electropolishing current detection device, a chucking mechanism for the polished object, and a vertical movement mechanism. (4) The apparatus for forming a needle-like object according to claim 3, wherein the vertical movement mechanism stops the tip of the object to be polished at a specific position below the electrolytic solution level with reference to the electrolytic solution level, and performs electrolytic polishing. .