Vacuum flash evaporated polymer composites

• US 5,681,615 A
• Filed: 07/27/1995
• Issued: 10/28/1997
• Est. Priority Date: 07/27/1995
• Status: Expired due to Term

• Current Assignee: Battelle Memorial Institute
• Original Assignee: Battelle Memorial Institute
• Inventors: Affinito, John D., Gross, Mark E.
• Primary Examiner(s): King, Roy V.
• Application Number:
  US08/508,278
• Time in Patent Office: 824 Days
• Field of Search: 427/255.6, 427/314, 427/565, 427/600
• US Class Current: 427/255.6
• CPC Class Codes: B05D 1/60 Deposition of organic layers from vapour phase vapour phase deposition in general C23C14/00, C23C16/00
• CPC Class Codes: H05K 3/0091 Apparatus for coating printed circuits using liquid non-metallic coating compositions

Abstract

A method for fabrication of polymer composite layers in a vacuum is disclosed. More specifically, the method of dissolving salts in a monomer solution, vacuum flash evaporating the solution, condensing the flash evaporated solution as a liquid film, and forming the condensed liquid film into a polymer composite layer on a substrate is disclosed.

Claims

1. A method for continuously supplying a uniform vapor of a polymerizable composite material in vacuum, said method comprising:

a) dissolving a salt in a monomer to form said polymerizable composite material,

b) supplying a continuous liquid flow of said composite material into a vacuum environment at a temperature below both the decomposition temperature and the polymerization temperature of the composite material,

c) continuously atomizing the liquid flow into a continuous flow of liquid droplets; and

d) continuously vaporizing said liquid droplets by causing said droplets to contact a heated surface which is maintained at a temperature at or above the boiling point for said composite material, but below the temperature at which said droplets would undergo pyrolysis before vaporizing.

2. A method for depositing onto a substrate in a vacuum environment a layer of polymerizable composite material, said material being characterized by the fact that it is chemically unstable at or below its boiling point, said method comprising:

a) dissolving a salt in a monomer to form said polymerizable composite material,

b) vaporizing said composite material into a vacuum environment by continuously placing droplets of said composite material into contact with a heated surface which is maintained at a temperature at or above the boiling point for said composite material, but below the temperature at which said droplets would undergo pyrolysis before vaporizing,

c) maintaining at least a portion of said substrate at a temperature which is below the boiling point of said composite material and in a region which is at a lower pressure than said vaporized composite material, to provide a positive flow of vaporized composite material toward said substrate; and

d) directing the flow of said vaporized composite material onto said substrate.

3. A method for depositing a layer of a polymerizable composite material on a substrate in a vacuum environment comprising:

a) dissolving a salt in a monomer to form said polymerizable composite material,

b) supplying a continuous liquid flow of said composite material into a vacuum environment at a temperature below both the decomposition temperature and the polymerization temperature of the composite material,

c) continuously atomizing the liquid flow into a continuous flow of liquid droplets;

d) continuously vaporizing said liquid droplets by causing said droplets to contact a heated surface which is maintained at a temperature at or above the boiling point for said composite material, but below the temperature at which said droplets would undergo pyrolysis before vaporizing,

e) maintaining at least a portion of said substrate at a temperature which is below the boiling point of said composite material and in a region which is at a lower pressure than said vaporized composite material, to provide a positive flow of vaporized composite material toward said substrate; and

f) directing the flow of said vaporized composite material onto said substrate.

4. A method for continuously supplying a uniform vapor of a polymerizable composite material in a vacuum environment, said method comprising:

a) dissolving a salt in a monomer to form said polymerizable composite material,

b) providing a liquid supply of said composite material in a vacuum environment at a temperature below both the decomposition temperature and the polymerization temperature of the composite material, to an end surface at a tip of an ultrasonic vibrating device,

c) ultrasonically vibrating said device so that the composite material supplied to the end surface coats the end surface and is dispersed in droplets from the periphery of the end surface; and

d) continuously vaporizing said liquid droplets by causing said droplets to contact a heated surface which is maintained at a temperature at or above the boiling point for said composite material, but below the temperature at which said droplets would undergo pyrolysis before vaporizing.