Method for manufacturing tunnel-effect sensors
AssigneeSiemens Aktiengesellschaft
InventorsEmmerich Bertagnolli, Markus Biebl
Life of this patent
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Abstract
In a method for manufacturing tunnel-effect sensors, a tip (2) composed of the silicon of the substrate (1) is produced on a substrate (1) of silicon with electrically conductively doped regions (4) by oxidation of the silicon using a nitride mask on the surface. Using the planarized oxide layer (5) produced in the oxidation step, a beam (3) of polysilicon that is anchored on the substrate (1) is applied, for example, over the tip (2) as a cooperating electrodes for the utilization of the tunnel effect and is electrically conductively doped. Subsequently, the oxide layer (5) is removed.
Claims6
A method for manufacturing tunnel-effect sensors on a substrate of silicon, the substrate being provided with a structure of electrical conductors produced by doping, a tip of silicon being produced on said substrate, comprising the steps of:
- in a first step, oxidizing a thin layer at a surface of the substrate to form a pad oxide layer;
- in a second step, applying and structuring a first mask of a material that prevents passage of oxygen onto the pad oxide layer;
- in a third step, upon employment of said first mask, oxidizing a layer at the surface of the substrate to form a first oxide layer;
- in a fourth step, nearly completely isotropically removing said first oxide layer, but such that the first mask remains in place;
- in a fifth step, providing a further pad oxide layer;
- in a sixth step, providing on said pad oxide layer a second mask from a layer of a material that prevents the passage of oxygen, that is isotropically applied surface-wide and that is structured;
- in a seventh step upon employment of said second mask, oxidizing a layer at the surface of the substrate to form an oxide layer, so that a tip arises under the second mask;
- in an eighth step, removing said second mask;
- and
- in a ninth step, removing said oxide layer.
A method for manufacturing tunnel-effect sensors on a substrate of silicon, the substrate being provided with a structure of electrical conductors produced by doping, a tip of silicon being produced on said substrate, comprising the steps of:
- in a first step, oxidizing a thin layer at a surface of the substrate to form a pad oxide layer;
- in a first further step, applying and structuring a first further mask of a material that prevents passage of oxygen onto the pad oxide layer, upon employment of said first further mask, oxidizing a layer at the surface of the substrate to form a first oxide layer, nearly completely isotropically removing said first oxide layer, but such that the first further mask remains in place, and providing a further pad oxide layer;
- in a second step, providing on said pad oxide layer a mask of a material that prevents passage of oxygen such that a layer of a material that prevents the passage of oxygen is isotropically applied surface-wide and is structured;
- in a third step upon employment of said mask, oxidizing a layer at the surface of the substrate to form an oxide layer, so that a tip arises under the ask;
- in a fourth step, removing said mask;
- in a fifth step, planarizing said oxide layer;
- and
- in a sixth step, removing said oxide layer.
Dependencies are inferred from the claim text.