Sensor chip and method for manufacturing a sensor chip

• US 9,140,740 B2
• Filed: 12/06/2013
• Issued: 09/22/2015
• Est. Priority Date: 09/02/2011
• Status: Active Grant

• Current Assignee: Sensirion AG (Sensirion Holding AG)
• Original Assignee: Sensirion AG (Sensirion Holding AG)
• Inventors: Hummel, Rene, Steiner-Vanha, Ralph, Bartsch, Ulrich
• Primary Examiner(s): AHMED, SELIM U
• Application Number:
  US14/099,153
• Publication Number:
  US 20140159745A1
• Time in Patent Office: 655 Days
• Field of Search: 257/414, 257/E21.001, 257/E29.166, 438/29
• US Class Current: 1/1
• CPC Class Codes: G01N 27/226 Construction of measuring vessels; Electrodes therefor
• CPC Class Codes: G01R 27/2605 Measuring capacitance capacitive sensors G01D5/24
• CPC Class Codes: H01L 23/5223 Capacitor integral with wiring layers
• CPC Class Codes: H01L 2924/00 Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
• CPC Class Codes: H01L 2924/0002 Not covered by any one of groups H01L24/00, H01L24/00 and H01L2224/00

Abstract

The present sensor chip comprises a substrate. A plurality of electrode elements is arranged at a first level on the substrate with at least one gap between neighboring electrode elements. A metal structure is arranged at a second level on the substrate, wherein the second level is different from the first level. The metal structure at least extends over an area of the second level that is defined by a projection of the at least one gap towards the second level.

Claims

1. Sensor chip, comprising

a substrate,

a plurality of electrode elements arranged at a first level on the substrate,

a plurality of gaps between neighbouring electrode elements,

a metal structure arranged at a second level on the substrate, wherein the second level is different from the first level,

wherein the metal structure extends over areas of the second level that are defined by projections of the gaps towards the second level, and wherein the gaps are at least partly filled with a dielectric material of a measuring layer for building a capacitive sensor,

wherein the chip includes at least n electrode elements and n−

1 gaps with n>

2, wherein the n electrode elements represent n electrode fingers of at least one electrode structure, and in particular wherein the n electrode elements represent n electrode fingers of two interdigitating electrode structures,

wherein the metal structure comprises multiple metal elements, wherein each metal element is assigned to one of the gaps for extending over an area of the second level that is defined by a projection of the assigned gap towards the second level and wherein each metal element covers an area between 10 percent smaller and 20 percent larger than that defined by the projection of the gap to which it is assigned.

2. Sensor chip according to claim 1, wherein the second level is arranged between the substrate and the first level.

3. Sensor chip according to claim 1, wherein each gap comprises at least an area in the first level confined by neighbouring electrode elements.

4. Sensor chip according to claim 3, wherein multiple of the electrode elements are arranged in parallel, and wherein the at least one gap has the form of a rectangle.

5. Sensor chip according to claim 1, wherein at least part of the metal structure is used as an electrode structure for interacting with one or more of the electrode elements.

6. Sensor chip according to claim 1,

comprising a protection layer covering the electrode elements and at least part of the metal structure, and wherein the measuring layer covers the protection layer.

7. Sensor chip according to claim 1, wherein the metal structure includes a shape complementary to a shape of the electrode elements in an area within outer electrode elements.