Device for protecting a chip and method for operating a chip

• US 20050095749A1
• Filed: 10/29/2004
• Published: 05/05/2005
• Est. Priority Date: 04/29/2002
• Status: Abandoned Application

• Current Assignee: Fraunhofer-Gesselschaft Zur Foederung Der Angewandten Forschung E.V.
• Original Assignee: Fraunhofer-Gesselschaft Zur Foederung Der Angewandten Forschung E.V.
• Inventors: Karlin, Tord, Krellmann, Mathias
• Application Number:
  US10/976,548
• Publication Number:
  US 20050095749A1
• Time in Patent Office: Days
• US Class Current: 438/107
• CPC Class Codes: G02B 26/0833 the reflecting element being a micromechanical device, e.g. a MEMS mirror, DMD G02B26/0825 takes precedence; micromechanical devices in general B81B

Abstract

A device for protecting a chip has a chamber adapted to receive the chip, a window allowing radiation to pass therethrough and to impinge the chip and a gas inlet. The gas inlet is in communication with the chamber and adapted to receive from a gas supply a gas flow, the gas flow protecting the chip.

Claims

1. Device (10) for protecting a chip (30) including at least one micromirror being displaceable in response to an applied signal, from a degradation due to a reaction of a portion of the chip with reaction components while being illuminated by a radiation, the device (10) comprising

a chamber (16) adapted to receive the chip (30);

and

a window (18) allowing the radiation to pass therethrough and to impinge at least on a portion of the chip (30);

wherein the chamber (16) comprises

a gas inlet (20) in communication with the chamber (16), the gas inlet (20) being adapted to receive from a gas supply (24) a gas flow, and in addition to the gas inlet, a gas outlet in communication with the chamber (16), the gas outlet being adapted to receive gas from the chamber (16).

2. Device (10) according to claim 1, wherein the reaction component is the oxygen contained in the ambient air, and wherein the gas flow provides a protection against oxidation of oxidizable parts of the chip (30) during operation of the chip (30) due to the radiation impinging on the chip (30).

3. Device (10) according to claim 1 or 2, wherein the chamber (12) allows gas to leak to an ambient atmosphere.

4. Device (10) according to any one of claims 1 to 3, wherein the window (18) is tilted with respect to a surface of the chip (30).

5. Device (10) according to any one of claims 1 to 4, wherein the window is adapted to transmit UV radiation.

6. Device (10) according to claim 5, wherein the window (18) is transparent to the UV radiation, the chip (30) comprising a micromirror containing aluminum or an aluminum alloy and an electrode for generating an electric force between the micromirror and the electrode for displacing the micromirror, the electrode formed of or containing TiN, the chip being mounted in a package.

7. Device (10) according to any one of claims 1 to 6, wherein the chamber (16) comprises means for an electrical connection of the chip (30) to a power supply outside the chamber (12).

8. Device (10) according to any one of claims 1 to 7, further comprising a housing (12, 12a, 12b) wherein the chamber (16) is formed by a recess in the housing (12, 12a, 12b).

9. Device (10) according to any one of claims 1 to 8, further comprising a housing including a chip housing (12a) and a top (12b) plate.

10. Method for operating a chip (30), the chip (30) comprising a micromirror containing aluminum or an aluminum alloy and an electrode for generating an electrical force between the micromirror and the electrode for displacing the micromirror, the method comprising the following steps:

applying a gas flow to the chip (30) for protecting the chip from degradation; and

illuminating the chip (30) while the gas flow is applied to the chip (30).

11. Method according to claim 10, wherein the radiation is an UV radiation.

12. Method according to claim 10 or 11, wherein the electrodes are formed of TiN, and the gas flow prevents an oxidation of the electrodes during an operation of the chip (30) due to radiation impinging on the chip (30).