Provided is a method for manufacturing a circuit board including: (a) preparing a mixture of a metal powder, an anti-sintering agent, and an activator; (b) immersing a dielectric substrate in the mixture; (c) forming a metal-containing layer on the surface of the dielectric substrate by heating the mixture under an inert atmosphere or under a reducing atmosphere; (d) forming a first metal layer on the metal-containing layer by electroless plating and forming a second metal layer thereon by electroplating; and (e) forming a metal pattern on the dielectric substrate, wherein the first metal layer includes Cu, Ni, Co, Au, Pd, or an alloy thereof, the second metal layer includes Cu, Ni, Fe, Co, Cr, Zn, Au, Ag, Pt, Pd, Rh, or an alloy thereof, and the method further includes performing heat treatment at least once after step (c).

A method for manufacturing an electrostatic chuck with multiple chucking electrodes made of ceramic pieces using metallic aluminum as the joining. The aluminum may be placed between two pieces and the assembly may be heated in the range of 770 C to 1200 C. The joining atmosphere may be non-oxygenated. After joining the exclusions in the electrode pattern may be machined by also machining through one of the plate layers. The machined exclusion slots may then be filled with epoxy or other material. An electrostatic chuck or other structure manufactured according to such methods.

An electrostatic chuck with a top surface adapted for Johnsen-Rahbek clamping in the temperature range of 500 C to 750 C. The top surface may be sapphire. The top surface is attached to the lower portion of the electrostatic chuck using a braze layer able to withstand corrosive processing chemistries. A method of manufacturing an electrostatic chuck with a top surface adapted for Johnsen-Rahbek clamping in the temperature range of 500 C to 750 C.

A sintered body includes a crystal grain containing silicon nitride, and a grain boundary phase. If dielectric losses of the sintered body are measured while applying an alternating voltage to the sintered body and continuously changing a frequency of the alternating voltage from 50 Hz to 1 MHz, an average value ε.sub.A of dielectric losses of the sintered body in a frequency band from 800 kHz to 1 MHz and an average value ε.sub.B of dielectric losses of the sintered body in a frequency band from 100 Hz to 200 Hz satisfy an expression |ε.sub.A−ε.sub.B|≤0.1.

An electrostatic chuck includes a ceramic top plate layer made of a beryllium oxide material, a ceramic bottom plate layer made of a beryllium oxide material, a ceramic middle plate layer disposed between the ceramic top plate layer and the ceramic bottom plate layer, an electrode layer disposed between the ceramic top plate layer and the ceramic middle plate layer, and a heater layer disposed between the ceramic middle plate layer and the ceramic bottom plate layer. The electrode layer joins and hermetically seals the ceramic top plate layer to the ceramic middle plate layer, and the heater layer joins and hermetically seals the ceramic middle plate layer to the ceramic bottom plate layer.

A method for producing a metal-ceramic substrate with a plurality of electrically conductive vias includes: attaching a first metal layer in a planar manner to a first surface side of a ceramic layer; after attaching the first metal layer, introducing a copper hydroxide or copper acetate brine into a plurality of holes in the ceramic layer delimiting a via, to form an assembly; converting the copper hydroxide or copper acetate brine into copper oxide; subjecting the assembly to a high-temperature step above 500° C. in which the copper oxide forms a copper body in the plurality of holes; and after converting the copper hydroxide or copper acetate brine into the copper oxide, attaching a second metal layer in a planar manner to a second surface side of the ceramic layer opposite the first surface side. The copper body produces an electrically conductive connection between the first and the second metal layers.

A bonded body of the present invention includes a ceramic member formed of ceramics and a Cu member formed of Cu or a Cu alloy. In a bonding layer formed between the ceramic member and the Cu member, an area ratio of a Cu.sub.3P phase in a region extending by up to 50 μm toward the Cu member side from a bonding surface of the ceramic member is equal to or lower than 15%.

A DBC substrate for power semiconductor devices includes a ceramic workpiece of a non-oxide ceramic having first and second opposing main sides, the ceramic workpiece having a thickness of 10 μm or more measured between the first and second main sides, a copper-containing layer disposed over the first main side, the copper-containing layer having a thickness of 5 μm or more, and an intermediate layer comprising Al.sub.2O.sub.3 disposed between the ceramic workpiece and the copper-containing layer.

A bonded body of the present invention includes a ceramic member formed of ceramics and a Cu member formed of Cu or a Cu alloy. In a bonding layer formed between the ceramic member and the Cu member, an area ratio of a Cu.sub.3P phase in a region extending by up to 50 μm toward the Cu member side from a bonding surface of the ceramic member is equal to or lower than 15%.

A method for the joining of ceramic pieces with a hermetically sealed joint comprising brazing a layer of joining material between the two pieces. The wetting and flow of the joining material is controlled by the selection of the joining material, the joining temperature, the joining atmosphere, and other factors. The ceramic pieces may be on a non-diffusable type, such as aluminum nitride, alumina, beryllium oxide, and zirconia, and the pieces may be brazed with an aluminum alloy under controlled atmosphere. The joint material is adapted to later withstand both the environments within a process chamber during substrate processing, and the oxygenated atmosphere which may be seen within the shaft of a heater or electrostatic chuck.