Periodic Reporting for period 2 - NEURODIAM (High density full diamond cortical implant for long life time implantation)
Okres sprawozdawczy: 2019-11-01 do 2021-04-30
NEURODIAM project
The goal of NEURODIAM project is to develop full diamond implant for neuronal applications (ex :cortical implants). The objectif is to solve two major challenges:
– increase the lifetime of implant by a specific packaging,
– reduce the size of the electrodes to be equivalent to the neurones size (10 μm) without degradation of noise and consequently increase the electrode density for a fine mapping of the cortex.
To avoid performance drift of the implant, a new completely hermetic packaging solution will be developed based on the last developments of micro and nano structuration of diamond layer that combines conductive and intrinsic synthetic diamond.
The goal of NEURODIAM project is to develop full diamond implant for neuronal applications (ex :cortical implants). The objectif is to solve two major challenges:
– increase the lifetime of implant by a specific packaging,
– reduce the size of the electrodes to be equivalent to the neurones size (10 μm) without degradation of noise and consequently increase the electrode density for a fine mapping of the cortex.
To avoid performance drift of the implant, a new completely hermetic packaging solution will be developed based on the last developments of micro and nano structuration of diamond layer that combines conductive and intrinsic synthetic diamond.
Concerning this first 18 months of the project, a new CVD diamond reactor has been installed in cleanroom. We developed several micro fabrication processes library to pattern diamond film to fabricate devices.
We settled first tested structures coated with combination of diamond intrinsic, doped diamond and metal. We continue to optimise processes to improve yield and performance of structures. We finalised ageing set-up and test structures and first full diamond structure has been tested. We tested this structure during 1.5 month. Diamond electrode has been stimulated during all this period (bi-phasic pulsed) and impedance recording every hour to follow evolution of structure. This first test shows a good stability of the structure during all experiments, however, they have displayed some soft issues (format of recording file, loss of information during recording) but we fixed them. We implemented temperature monitoring to achieve accelerating ageing test.
We began development of wireless electronic to done impedance measurements. For this prototype we used commercial integrated circuit. That gave us a mean to reduce development time and achieves a functional system. The prototype is fully functional with HMI, data storage on computer and wireless communication. The size of device is too large to be wearing on small animal (rat model) and used in chronic, but it can be used in acute. We now work of shrinking electronic and increase frequency band.
We settled first tested structures coated with combination of diamond intrinsic, doped diamond and metal. We continue to optimise processes to improve yield and performance of structures. We finalised ageing set-up and test structures and first full diamond structure has been tested. We tested this structure during 1.5 month. Diamond electrode has been stimulated during all this period (bi-phasic pulsed) and impedance recording every hour to follow evolution of structure. This first test shows a good stability of the structure during all experiments, however, they have displayed some soft issues (format of recording file, loss of information during recording) but we fixed them. We implemented temperature monitoring to achieve accelerating ageing test.
We began development of wireless electronic to done impedance measurements. For this prototype we used commercial integrated circuit. That gave us a mean to reduce development time and achieves a functional system. The prototype is fully functional with HMI, data storage on computer and wireless communication. The size of device is too large to be wearing on small animal (rat model) and used in chronic, but it can be used in acute. We now work of shrinking electronic and increase frequency band.
The goal of this project is to breakthrough the limit of neuronal implants (no stable impmlant for chronic application) and we propose a new route to fabricat long term stable implants for functional rehabilitation (ex cortical implant).
To do this we propose to use diamond material. Diamond is a very attractive for bio applications : no native oxide, chemical inert and concerning doped dimond high electrochemical window.
We fabricated strips to test stability of diamond structure and at the end of this period we started the fabrication our first full diamond implants.
At the end of the project we will propose a soft full diamond implant with a long term stability for chronic neuronal implant.
This technology devlop in this project will have to several applications for neuroncal diseases. We will be able to develop a specific cortical implants for blind or tetraplagic patients to help these patient to recover vison or autonomous. We will be able to imagine another applicatons with this technology to provide medical devices for cardiac or muscular applications.
To do this we propose to use diamond material. Diamond is a very attractive for bio applications : no native oxide, chemical inert and concerning doped dimond high electrochemical window.
We fabricated strips to test stability of diamond structure and at the end of this period we started the fabrication our first full diamond implants.
At the end of the project we will propose a soft full diamond implant with a long term stability for chronic neuronal implant.
This technology devlop in this project will have to several applications for neuroncal diseases. We will be able to develop a specific cortical implants for blind or tetraplagic patients to help these patient to recover vison or autonomous. We will be able to imagine another applicatons with this technology to provide medical devices for cardiac or muscular applications.