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US 5,038,322 AGranted
Method of and device for sub-micron processing a surface
AssigneeU.S. Philips Corporation
InventorEvert J. Van Loenen
Life of this patent
Estimating the term…
Abstract
A method of and a device for sub-micron deforming a surface (15) is described, for example for the purpose of inscribing information. During scanning of the surface the tip (14) of a scanning tunneling microscrope is held at a constant distance from the surface by means of a negative feedback control loop (18) which is controlled by a tunneling current (It) between the tip and the surface, and for forming a pit (21) in the surface (15). The control loop is deactivated and a tip height drive member (8) is energized by means a control voltage (Vpz) whose amplitude increases as a function of time and which has a predetermined final value, such that the tip is lowered into the material.
Claims12
A method of deforming a surface on a sub-micron scale by using a tip of a scanning tunneling microscope (STM) comprising the steps of
- a) moving a tip of a STM in a pattern in a scanning direction in a plane parallel to a surface of an object to form a processing pattern on said surface;
- b) holding said tip at a reference level above said surface upon moving said tip in said pattern by applying a first electrical control voltage to a tip height driving arrangement, said reference level being at a constant distance from said surface;
- c) supplying voltage to said tip height driving arrangement through a negative feedback control loop, said negative feedback control loop being controlled by a tunneling current resulting from a constant tunneling voltage applied between said tip and said surface;
- d) deforming said surface by the substeps of
- (i) interrupting said negative feedback control loop,
- (ii) energizing said tip height driving arrangement with a second electrical control voltage,
- (iii) increasing amplitude of said second electrical control voltage as a function of time to lower said tip from said reference level into said surface to a defined level, and
- (iv) producing a pit in said surface with said tip at said defined level, said pit having an accurately defined geometry;
- e) thereafter retracting said tip to said reference level above said surface by switching-on said negative feedback control loop;
- and
- f) then repeating said steps (c)-(e) to form subsequent pits in said pattern in said surface.
8 more elements
An apparatus for deforming a surface on a sub-micron scale comprising
- a) holding means for holding an object having a surface,
- b) a thin conducting stylus having a tip,
- c) first and second drive means for respectively moving said stylus and said holding means relative to one another in two mutually perpendicular directions parallel to a plane of said surface,
- d) tip height driving means for adjusting distance between said tip and said surface,
- e) negative feedback control loop means for applying a first control voltage to said tip height driving means,
- f) electronic circuit means including
- (i) input means for receiving an electrical signal, said electrical signal providing information about a pattern to be provided on said surface,
- (ii) first and second output means for respectively supplying a first and a second control signal, said first and second output means being connected respectively to said first and second drive means, and
- (iii) third output means for supplying a signal to temporarily interrupt said negative feedback control loop means during given time intervals, and
- g) voltage source means for supplying a second control voltage to said tip height driving means during said given time intervals, said second control voltage having an amplitude increasing with time to a predetermined final voltage value, said final voltage value being larger than said first control voltage.
7 more elements
An apparatus for inscribing and reading information from a record carrier surface comprising
- a) a record carrier having a surface for disposing a succession of separated information pits;
- and
- b) a device for inscribing information in the form of said succession of separated information pits, said device comprising
- c) holding means for holding an object having a surface,
- d) a thin conducting stylus having a tip,
- e) first and second drive means for respectively moving said stylus and said holding means relative to one another in two mutually perpendicular directions parallel to a plane of said surface,
- f) tip height driving means for adjusting distance between said tip and said surface,
- g) negative feedback control loop means for applying a first control voltage to said tip height driving means,
- h) electronic circuit means including
- (i) input means for receiving an electrical signal, said electrical signal providing information about a pattern to be provided on said surface,
- (ii) first and second output means for respectively supplying a first and a second control signal, said first and second output means being connected respectively to said first and second drive means, and
- (iii) third output means for supplying a signal to temporarily interrupt said negative feedback control loop means during given time intervals, and
- i) voltage source means for supplying a second control voltage to said tip height driving means during said given time intervals, said second control voltage having an amplitude increasing with time to a predetermined final voltage value, said final voltage value being larger than said first control voltage;
- wherein said device includes reading means for reading the inscribed information, said reading means controlling said tip height driving means by one of said first control voltage or a control voltage being independent of information on said surface.
11 more elements
Dependencies are inferred from the claim text.