Sealed-type remote pressure-monitoring device and method for fabricating the same

• US 6,517,483 B2
• Filed: 01/04/2001
• Issued: 02/11/2003
• Est. Priority Date: 09/03/1998
• Status: Expired due to Fees

• Current Assignee: Korea Advanced Institute of Science and Technology
• Original Assignee: Korea Advanced Institute of Science and Technology
• Inventors: Yoon, Jun-Bo, Yoon, Euisik, Park, Eun-Chul
• Primary Examiner(s): Hindenburg, Max
• Assistant Examiner(s): WINGOOD, PAMELA LYNN
• Application Number:
  US09/755,911
• Publication Number:
  US 20010001311A1
• Time in Patent Office: 768 Days
• Field of Search: 600/373-404
• US Class Current: 600/398
• CPC Class Codes: A61B 2562/028 Microscale sensors, e.g. electromechanical sensors [MEMS]
• CPC Class Codes: A61B 3/16 for measuring intraocular pressure, e.g. tonometers

Abstract

Disclosed are a remote pressure-monitoring device and a preparing method thereof. The device comprises a metal electrode on a glass substrate, a capacitive sensor made of a silicon diaphragm, and an electroplated inductor electrically connected, in parallel, with the sensor. The glass substrate and the silicon are electrically bonded to form an LC resonator. For the fabrication of the device, first, a metal electrode which plays a role as a lower electrode for a capacitive pressure sensor is deposited on the glass substrate with the same coefficient of thermal expansion as that of silicon. An inductor is formed at a thickness by copper electroplating, surrounding the metal electrode at a predetermined distance. A silicon substrate is anisotropically etched to form a space for enveloping the metal electrode at a central area and to form a groove around the space. Boron ions are diffused lightly into the space and deeply into the groove to form etch barriers thereat, followed by bonding the silicon substrate on the glass substrate through an electrical contact in such a way that the metal electrode and the inductor are enveloped in the space and the groove, respectively. Then, the silicon substrate is etched out from its rear side to the extent that the etch barriers are exposed.

Claims

1. A device for remote monitoring the internal pressure of animal organs, said device comprising:

a glass substrate having a coefficient of thermal expansion as large as that of silicon;

a metal electrode which is formed at a predetermined thickness on a central area of the glass substrate;

an inductor which is formed at a predetermined thickness on the glass substrate by a copper electroplating process, surrounding the metal electrode at a predetermined distance;

a silicon cover, consisting of a silicon diaphragm and a cover structure, which is bonded on the glass substrate in such a manner that the silicon diaphragm and the cover structure cover the metal electrode and the inductor, respectively, without a direct contact between them, thereby shielding the metal electrode and the inductor from the external environment;

a contact which is formed on the glass substrate, extending from a junction between the glass substrate and the silicon cover to the inductor to electrically connect the silicon cover to the inductor.