Abstract:
A method for manufacturing a semiconductor substrate (7) of a first concentration type is described, which comprises at least a buried insulating cavity (10b, 10d), comprising the following steps:
form on the semiconductor substrate (7) a plurality of trenches (8, 10), form a surface layer (7a, 9a) on the semiconductor substrate in order to close superficially the plurality of trenches (8, 10) forming in the meantime at least a buried cavity (10b) in correspondence with the surface-distal end of the trenches (8, 10).
Devices manufactured with the method according to the invention are also described.
Abstract:
A semiconductor substrate comprising at least a buried insulating cavity (10b, 10d) and comprising: - a semiconductor substrate (7) having a first type of concentration and having a plurality of trenches (8, 10), - a surface layer (7a, 9a) on said semiconductor substrate (7) in order to close superficially said plurality of trenches (8, 10) forming said at least a buried insulating cavity (10b, 10d); - a first semiconductor material layer (9) on said surface layer (7a, 9a) having the same first type of concentration as said semiconductor substrate (7), said first semiconductor material layer (9) comprising at least a trench (11) which is in communication with said at least a buried insulating cavity (10b, 10d).
Abstract:
A planarly integrated fuel cell structure, formed in a region (2) preliminarily rendered pervious to fluid flow and electrically nonconductive of the monocrystalline silicon substrate (1), has at least a pair of parallel channels, an anode feed channel (3) and a cathode feed channel (4), respectively, extending in the oxidized porous oxidized silicon region and defining a central oxidized porous silicon ridge (5) therebetween; a dielectric cap (B, P, 6b, 17) over said channelled oxidized porous silicon region (2), having at least an inlet and an outlet hole (11-12, 13-14) formed therethrough in correspondence of one end and the opposite end, respectively, of each one of the parallel channels (3, 4) underneath, for separately circulating a fluid fuel in the anode channel (3) and air or other oxygen containing mixture in the cathode channel (4); a pair of parallel spaced solid metal cell electrodes (7, 8) extending over the top surface of said central oxidized porous silicon ridge (5) defined between said parallel channels (3, 4), for the whole length of the channels; cathodically deposited uninterrupted electrically conductive threads (7', 8') of a catalytic metal, stemming from a bottom surface of each of said solid metal cell electrodes (7, 8) and extending to the side face of said central ridge (5) of oxidized porous silicon constituting a side wall of the channel (3, 4) extending alongside of the electrode (7, 8); ion permeable resin filling the pores of the nonconductive porous silicon in the innermost central portion of the ridge (5) to impede fluid flow from one channel (3) to the other (4), and only partly filling the pores in proximity of the definition sides of said central ridge (5) constituting side walls of one and of the other of said parallel channels (3, 4), forming uninterrupted ion permeable resin domains extending from catalytic metal threads (7') stemming from one solid metal cell electrode (7) to catalytic metal threads (8') stemming from the other solid metal cell electrode (8); and means for electrically connecting said two parallel solid metal cell electrodes (7, 8) to a load circuit of the cell.
Abstract:
A semiconductor substrate comprising at least a buried insulating cavity (10b, 10d) and comprising: - a semiconductor substrate (7) having a first type of concentration and having a plurality of trenches (8, 10), - a surface layer (7a, 9a) on said semiconductor substrate (7) in order to close superficially said plurality of trenches (8, 10) forming said at least a buried insulating cavity (10b, 10d); - a first semiconductor material layer (9) on said surface layer (7a, 9a) having the same first type of concentration as said semiconductor substrate (7), said first semiconductor material layer (9) comprising at least a trench (11) which is in communication with said at least a buried insulating cavity (10b, 10d).
Abstract:
A planarly integrated fuel cell structure, formed in a region (2) preliminarily rendered pervious to fluid flow and electrically nonconductive of the monocrystalline silicon substrate (1), has at least a pair of parallel channels, an anode feed channel (3) and a cathode feed channel (4), respectively, extending in the oxidized porous oxidized silicon region and defining a central oxidized porous silicon ridge (5) therebetween; a dielectric cap (B, P, 6b, 17) over said channelled oxidized porous silicon region (2), having at least an inlet and an outlet hole (11-12, 13-14) formed therethrough in correspondence of one end and the opposite end, respectively, of each one of the parallel channels (3, 4) underneath, for separately circulating a fluid fuel in the anode channel (3) and air or other oxygen containing mixture in the cathode channel (4); a pair of parallel spaced solid metal cell electrodes (7, 8) extending over the top surface of said central oxidized porous silicon ridge (5) defined between said parallel channels (3, 4), for the whole length of the channels; cathodically deposited uninterrupted electrically conductive threads (7', 8') of a catalytic metal, stemming from a bottom surface of each of said solid metal cell electrodes (7, 8) and extending to the side face of said central ridge (5) of oxidized porous silicon constituting a side wall of the channel (3, 4) extending alongside of the electrode (7, 8); ion permeable resin filling the pores of the nonconductive porous silicon in the innermost central portion of the ridge (5) to impede fluid flow from one channel (3) to the other (4), and only partly filling the pores in proximity of the definition sides of said central ridge (5) constituting side walls of one and of the other of said parallel channels (3, 4), forming uninterrupted ion permeable resin domains extending from catalytic metal threads (7') stemming from one solid metal cell electrode (7) to catalytic metal threads (8') stemming from the other solid metal cell electrode (8); and means for electrically connecting said two parallel solid metal cell electrodes (7, 8) to a load circuit of the cell.