Method for fabricating a channel device and tube connection

• US 5,027,499 A
• Filed: 04/21/1989
• Issued: 07/02/1991
• Est. Priority Date: 12/09/1985
• Status: Expired due to Fees

• Current Assignee: OTTO Sensors Corporation
• Original Assignee: OTTO Sensors Corporation
• Inventors: Prohaska, Otto J.
• Primary Examiner(s): Eley, Timothy V.
• Assistant Examiner(s): VO, PETER DUNG BA
• Application Number:
  US07/341,641
• Time in Patent Office: 802 Days
• Field of Search: 29/593, 29/423, 29/424, 29/852, 29/853, 29/846, 29/595, 156/644, 156/656, 156/659.1, 156/661.1, 156/901, 156/902, 204/406, 204/411, 204/424, 204/425, 427/96, 427/97, 427/264, 427/265, 73/864.83, 73/864.84, 73/866, 73/863.84
• US Class Current: 29/595
• CPC Class Codes: G01F 1/6847 where sensing or heating elements are not disturbing the fluid flow, e.g. elements mounted outside the flow duct
• CPC Class Codes: G01N 11/02 by measuring flow of the material
• CPC Class Codes: G01N 21/17 Systems in which incident light is modified in accordance with the properties of the material investigated where the material investigated is optically excited causing a change in wavelength of the incident light G01N21/63
• CPC Class Codes: G01N 21/41 Refractivity; Phase-affecting properties, e.g. optical path length G01N21/21 takes precedence
• CPC Class Codes: G01N 21/85 Investigating moving fluids or granular solids
• CPC Class Codes: G01N 2201/0622 Use of a compensation LED
• CPC Class Codes: G01N 25/18 by investigating thermal conductivity by calorimetry G01N25/20; by measuring change of resistance of an electrically-heated body G01N27/18
• CPC Class Codes: G01N 27/221 by investigating the dielectric properties using microwaves G01N22/00; measuring loss factors or dielectric constants per se G01R27/26
• CPC Class Codes: G01N 30/6052 body
• CPC Class Codes: G01N 30/6095 Micromachined or nanomachined, e.g. micro- or nanosize
• CPC Class Codes: Y10T 29/49007 Indicating transducer
• CPC Class Codes: Y10T 29/49812 Temporary protective coating, impregnation, or cast layer

Abstract

The invention is concerned with a method for manufacturing a channel device, especially for recordings of thermal conductivity, viscosity, density, dielectric constants, refractive indices, etc. of materials such as fluids and gases (called samples), where the material under investigation is guided through a measuring channel with at least one sensor and at least one inlet and one outlet orifice for the sample. The invention also concerns the fabrication procedure of the channel device, especially the recording unit for determining the thermal conductivit, viscosity, density, dielectric constant, etc. of samples where the material under investigation is passed through or brought into a measuring channel which is equipped with sensors and actuators.

Claims

1. A method for manufacturing a device for measuring at least one characteristic of a fluid by passing such fluid through a measuring channel of appropriate dimensions for measuring such characteristic;

said method comprising the steps of;

providing a support member having an inlet orifice and an outlet orifice;

depositing a channel-forming dissolvable material on the support member in a path which spans between the inlet and outlet orifices;

controlling the shape of the path of dissolvable material to obtain a measuring channel having appropriate dimensions for measuring said one characteristic of the fluid;

forming a wall by depositing a wall-forming material onto the support member and onto and around the path of passage-forming dissolvable material by a process selected from a group consisting of evaporation, spin on, drop on, sputtering, and reactive deposition, whereby a wall is formed which substantially covers the path of channel-forming dissolvable material and which covers at least parts of the support member;

dissolving and removing the path of channel-forming dissolvable material through at least one of said orifices by introducing a solvent which dissolves the path of dissolvable material but which does not interact with the support member and the wall, whereby a measuring channel of appropriate dimensions is formed which spans between the inlet orifice and the outlet orifice, whereby inner surfaces of the support member and the wall define the measuring channel and whereby the support member and wall form a housing surrounding the measuring channel; and

providing at least one sensor for measuring at least one characteristic of such fluid as it passes through the measuring channel by attaching and arranging the sensor in a sensing position relative to the housing by a process which is a member of a group consisting of evaporation, spin on, drop on, sputtering, reactive deposition, chemical vapor deposition, plasma enhanced chemical vapor deposition, and ion implantation whereby the housing and sensor form a sensor-housing unit.

2. The method as set forth in claim 1 wherein the step of forming the wall includes depositing on the dissolvable material a material selected from a group consisting of synthetic resin, glass, ceramic Si₃ N₄, SiO₂, SiO, and combinations thereof.

3. The method as set forth in claim 1 further comprising the step of depositing a cover layer on top of at least a portion of said sensor-housing unit.

4. The method as set forth in claim 1 further comprising the step of etching the inner surfaces of the support surface and the wall which define the measuring channel.

5. The method as set forth in claim 1 further comprising the step of passivating the inner surfaces of the support surface and the wall defining the measuring channel.

6. The method as set forth in claim 1 wherein said step of providing a support member includes providing a substrate having two openings, one opening forming the inlet orifice and the other opening forming the outlet orifice.

8. The method as set forth in claim 1 wherein said step of dissolving and removing includes the step of removing said dissolvable material through at least one of said orifices.

9. The method as set forth in claim 1 wherein said step of providing a support surface includes the steps of:

providing a substrate;

attaching a plurality of tubes to the substrate to form a plurality of inlet orifices; and

attaching a plurality of tubes to the substrate to form a plurality of outlet orifices.

10. The method as set forth in claim 1 wherein said step of providing a support member comprises the steps of providing a substrate;

and attaching at least one tube to the substrate to form at least one of said orifices, and wherein the step of forming the wall includes the step of depositing the channel-forming dissolvable material on at least a portion of the tube.

11. The method as set forth in claim 10 wherein the step of attaching at least one tube to the substrate includes the step of attaching a tube having a nozzle-like opening.

12. The method as set orth in claim 10 further comprising the step of forming an indentation in the substrate for receiving the one tube.

7. The method as set forth in claim wherein said step of providing a support member includes the steps of:

providing a substrate;

attaching a first tube to the substrate to form the inlet orifice; and

attaching a second tube to the substrate to form the outlet orifice.

13. A method of manufacturing a device for measuring at least one characteristic of a fluid by passing such fluid through a measuring channel of appropriate dimensions for measuring such characteristic, said method comprising the steps of:

providing a substrate;

attaching at least one tube to the substrate to form a first orifice;

providing the substrate with a second orifice;

depositing a channel-forming dissolvable material on the substrate in a path which is of a shape corresponding to such appropriate dimensions of such measuring channel of the measuring device and which spans between the first and second orifices;

depositing a wall-forming material onto the path of the passage-forming dissolvable material and onto a portion of the tube by a process selected from a group consisting of evaporation, spin on, drop on, sputtering, reactive deposition, whereby a wall is formed which substantially covers the path of channel-forming dissolvable material and which covers a portion of the tube;

dissolving and removing the channel-forming dissolvable material through at least one of the orifices by introducing a solvent which is capable of dissolving the dissolvable material but which does not interact with the substrate and the wall whereby the measuring channel of appropriate dimensions is formed which spans between the first and second orifices, and whereby the substrate, the tube and the wall form a housing surrounding the measuring channel;

providing at least one sensor for measuring such one characteristic of such fluid as it passes through the measuring channel by attaching and arranging the sensor in a sensing position relative to the housing by a process selected from a group consisting of evaporation, spin on, drop on, sputtering, reactive deposition, chemical vapor deposition, plasma enhanced chemical vapor deposition, and ion implantation.

14. The method as set forth in claim 13 wherein said step of dissolving and removing includes the step of removing said dissolvable material through at least one of said orifices.

15. A method for manufacturing a device for measuring at least one characteristic of a fluid, said device having a wall defining a measuring channel of a certain shape, an inlet orifice and an outlet orifice for conducting fluid into and out of the measuring channel, and at least one sensor for measuring at least one characteristic so the fluid which flows through the measuring channel, said method comprising the steps of:

providing a support member having an inlet orifice and an outlet orifice;

depositing a channel-forming dissolvable material on the support member in a path which spans between the inlet and outlet orifices and having a shape corresponding to the shape of the measuring channel of the measuring device;

controlling the shape of the path of dissolvable material to obtain a measuring channel having appropriate dimensions for measuring said one characteristic of the fluid;

forming a wall by depositing a wall-forming material onto the support member and onto and around the path of passage-forming dissolvable material by a process selected from a group consisting of evaporation, spin on, drop on, sputtering, and reactive deposition, whereby a wall is formed which substantially covers the path of channel-forming dissolvable material and which covers at least parts of the support member;

wherein this step of forming the wall includes depositing on the first body of dissolvable material the second body of material selected from a group consisting of synthetic resin, glass, ceramic Si₃ N₄, SiO₂, SiO, and combinations thereof;

dissolving and removing the path of channel-forming dissolvable material through at least one of said orifices by introducing a solvent which dissolves the path of dissolvable material but which does not interact with the support member and the wall, whereby a measuring channel of appropriate dimensions is formed which spans between the inlet orifice and the outlet orifice, whereby inner surfaces of the support member and the wall define the measuring channel and whereby the wall and the support member form a housing surrounding the measuring channel; and

arranging and attaching at least one sensor in a sensing position relative to the housing by a process which is a member of group consisting of evaporation, spin on, drop on, sputtering, reactive deposition, chemical vapor deposition, plasma enhanced chemical vapor deposition, and ion implantation whereby the housing and sensor together form a sensor-housing unit; and

depositing a cover layer on top of at least a portion of said sensor-housing unit.