MHCD and microfluidic apparatus and method

A microhollow cathode discharge and microfluidic assembly comprising:

• a substrate;
• a dielectric body and layers of conductive material integrated on the substrate and defining a microhollow cathode discharge cavity, the microhollow cathode discharge cavity capable of containing an environment for carrying a gas discharge within the microhollow cathode discharge cavity to generate a gas based electromagnetic wave;
• electrical connections coupled to the layers of conductive material for applying a cathode discharge potential to the layers of conductive material;
• a microfluidic channel integrated on the substrate, a portion of the channel being formed of conductive material for conducting the electromagnetic wave;
• and
• an electromagnetic path extending from the microhollow cathode discharge cavity laterally through the portion of the microfluidic channel.

A microhollow cathode discharge and microfluidic assembly comprising:

• a plurality of layers of ceramic material each having an opening extending therethrough, at least some of the plurality of layers having conductive material thereon defining electrodes surrounding the opening and vias filled with conductive material connected to the electrodes, two layers of the plurality of layers further having conductive material extending to form an external contact, the plurality of layers being fired into an integral ceramic unit defining a microhollow cathode discharge cavity with spaced apart and interconnected electrodes and electrical connections coupled to the electrodes for applying a cathode discharge potential to the electrodes;
• an environment capable of carrying a gas discharge within the microhollow cathode discharge cavity to generate a gas based electromagnetic wave;
• a microfluidic channel integrated with the integral ceramic unit, a portion of the channel being formed of conductive material for conducting the electromagnetic wave from the cavity;
• and
• an electromagnetic path extending from the microhollow cathode discharge cavity laterally through the portion of the microfluidic channel.

A method of fabricating a microhollow cathode discharge and microfluidic assembly comprising the steps of:

• providing a plurality of layers of dielectric material each having an opening extending therethrough, at least some of the plurality of layers having conductive material thereon defining electrodes surrounding the opening and conductive material extending to form electrical contacts;
• fixing the plurality of layers of material together in overlying relationship to form a stack with the openings aligned, the stack defining a microhollow cathode discharge cavity with spaced apart and interconnected electrodes and electrical connections coupled to the electrodes for applying a cathode discharge potential to the electrodes, the microhollow cathode discharge cavity being capable of containing an environment for carrying a gas discharge within the microhollow cathode discharge cavity to generate a gas based electromagnetic wave;
• providing a channel designed to carry a sample to be interrogated;
• and
• coupling the electromagnetic emission to the channel for interrogating at least one physico-chemical property of a sample carried by the channel.

A method of fabricating a microhollow cathode discharge and microfluidic assembly comprising the steps of:

• providing a plurality of layers of unfired ceramic material each having an opening extending therethrough, at least some of the plurality of layers having conductive material thereon defining electrodes surrounding the opening and vias filled with conductive material connected to the electrodes, two layers of the plurality of layers further having conductive material extending to form electrical contacts;
• stacking the plurality of layers of unfired ceramic material in overlying relationship to form a stack with the openings aligned;
• heating and applying a pressure to the stack to fixedly bond the plurality of layers in the stack together;
• firing the stack to cure the plurality of layers of unfired ceramic material into an integral ceramic unit defining a microhollow cathode discharge cavity with spaced apart and interconnected electrodes and electrical connections coupled to the electrodes for applying a cathode discharge potential to the electrodes;
• integrating a microfluidic channel with the integral ceramic unit, a portion of the channel being formed of conductive material for electromagnetic emissions;
• and
• providing an electromagnetic emissions path extending from the microhollow cathode discharge cavity laterally through the portion of the microfluidic channel.

A method of utilizing a microhollow cathode discharge and microfluidic assembly comprising the steps of:

• providing a microhollow cathode discharge cavity with spaced apart and interconnected electrodes and electrical connections coupled to the electrodes for applying a cathode discharge potential to the electrodes, the microhollow cathode discharge cavity being capable of containing an environment for carrying a gas discharge within the microhollow cathode discharge cavity to generate a gas based electromagnetic wave;
• providing a channel designed to carry a sample to be interrogated;
• and
• coupling the electromagnetic emission to the channel for interrogating at least one physico-chemical property of a sample carried by the channel.