S.o.i.tec Silicon on Insulator Technologies

S.o.i. Tec Silicon on Insulator Technologies, S.a.

Soitec

Muriel Martinez

Olivier Rayssac

Thierry Barge

Chrystelle Lagahe-Blanchard

Alain Soubie

Cécile Berne

Sephorah Bisson

Lionel Portigliatti

Patrick Reynaud

Alice Boussagol

Frédéric Metral

Zohra Chahra

Pierre Bey

The invention relates to improvements in the polishing of a layer of germanium by a method which includes a first step of chemical-mechanical polishing of the surface of the germanium layer that is carried out with a first polishing solution having an acidic pH. The first polishing step is then followed by a second step of chemical-mechanical polishing of the surface of the germanium layer carried out with a second polishing solution having an alkaline pH. The polished heteroepitaxial germanium layer has a surface microroughness of less than 0.1 nm RMS and a surface macroroughness corresponding to a surface haze level of less than 0.5 ppm.

Germanium layer polishing

A method of planarization of a surface of a heteroepitaxial layer by chemical-mechanical polishing the disturbed surface of the heteroepitaxial layer with a polishing pad having a compressibility greater than 2% and less than 15% and a slurry comprising at least 20% of silica particles having an average diameter between about 70 and about 100 nm. This method allows to reach high polishing rates appropriated for eliminating surface defects on heteroepitaxial layers, such as crosshatch patterns, and to achieve, in the same time, a final polish that is desirable to facilitate further operations.

Planarization of a heteroepitaxial layer

An automatic high-precision layer cutting device for separating a layer from a semiconductor substrate. The device includes a fixed positioning member for receiving at least a portion of a semiconductor substrate that has a weakened area therein and a peripheral annular notch located below the weakened area. The positioning member maintains the position of the substrate on a moveable support. A cutting mechanism having at least one blade is provided for contacting the substrate and inducing a cleaving wave therein. The cutting mechanism is operatively associated with the positioning member so that the as at least one blade contacts the annular notch, the positioning member prevents movement of the substrate and the moveable support moves away from the substrate to allow the cleaving wave to both divide the substrate at the notch into first and second parts and detach the layer from the substrate along the weakened area.

Substrate layer cutting device and method

A semiconductor structure includes a substrate having a surface and being made of a material that provides atypical surface properties to the surface, a bonding layer on the surface of the substrate, and a further layer molecularly bonded to the bonding layer. A method for fabricating such a semiconductor structure includes providing a substrate having a surface and being made of a material that provides atypical surface properties to the surface, providing a bonding layer on the surface of the substrate, smoothing the bonding layer to provide a surface that is capable of molecular bonding, and molecularly bonding a further layer to the bonding layer to form the structure. The atypical surface properties preferably include at least one of a roughness of more than 0.5 nm rms, or a roughness of at least 0.4 nm rms that is difficult to polish, or a chemical composition that is incompatible with molecular bonding.

Semiconductor structure and method of making same

An automatic high-precision layer cutting device for separating a layer from a semiconductor substrate. The cutting device includes a fixed positioning member for receiving at least a portion of a semiconductor substrate that has a weakened area therein and a peripheral annular notch that is located below the weakened area. The positioning member maintains a predetermined position of the substrate on a support. The device also includes cutting means having at least one blade for contacting the substrate and for inducing a cleaving wave into the substrate. The cutting means is operatively associated with the positioning member so that the at least one blade contacts the annular notch and the positioning member prevents movement of the substrate. The at least one blade induces a cleaving wave of sufficient intensity to both divide the substrate at the notch into first and second parts and detach the layer from the substrate along the weakened area.

A semiconductor structure includes a substrate having a surface and being made of a material that provides a typical surface properties to the surface, a bonding layer on the surface of the substrate, and a further layer molecularly bonded to the bonding layer. A method for fabricating such a semiconductor structure includes providing a substrate having a surface and being made of a material that provides a typical surface properties to the surface, providing a bonding layer on the surface of the substrate, smoothing the bonding layer to provide a surface that is capable of molecular bonding, and molecularly bonding a further layer to the bonding layer to form the structure. The a typical surface properties preferably include at least one of a roughness of more than 0.5 nm rms, or a roughness of at least 0.4 nm rms that is difficult to polish, or a chemical composition that is incompatible with molecular bonding.

The present invention relates to a method for forming a heterogeneous assembly of first and second materials having different coefficients of thermal expansion. The method includes bonding a surface of a first substrate of a first material to a surface of a second substrate of a second material wherein the first substrate includes a zone of weakness therein to define a transfer layer adjacent the first surface, providing a stiffening substrate of a third material to maintain sufficient flatness and prevent breakage of the transfer layer during detachment from the first substrate, and detaching the transfer layer from the first substrate along the zone of weakness to form a heterogeneous assembly of the transfer layer and second substrate. The stiffening substrate is bonded to one of the first or second substrates and the third material has a coefficient of thermal expansion that is the same as or close to that of the material of the substrate to which the stiffening substrate is bonded to facilitate a successful detachment of the transfer layer from the first substrate.

Growing community of inventors

St Egreve, France

Muriel Martinez