Palo Alto Research Center Inc.

Michal V Wolkin

Ana Claudia Arias

Dirk De Bruyker

Eric Peeters

Francisco Eduardo Torres

Richard H Bruce

Alan G Bell

Eugene Michael Chow

Gregory B Anderson

A thin substrate has a layered structure on one surface, and can also have a layered structure on the other. Each layered structure can include a part of at least one patterned layer that, if patterned by photolithography, would frequently result in damage to the substrate due to fragility. For example, the substrate could be a 3 mil (76.2 &#x3bc;m) or thinner polyimide film and one patterned layer could be a semiconductor material such as vanadium oxide, while another could be metal in electrical contact with semiconductor material. The layer part, however, can be patterned by a printing operation or can include a printed patterned artifact such as an uneven boundary or an alignment. The printing operation can be direct printing or printing of a mask for etching or liftoff or both. The layered structure can include an array of cells, each with layer parts on each substrate surface.

Layered structures on thin substrates

Method for producing layered structures on thin substrates

A nanocalorimeter includes a merging layer having, a drop placement area for holding drops to be merged and a thermal equilibration area. A measurement layer includes a substrate, and a temperature probe on the substrate, wherein the temperature probe extends out of the surface of the substrate to come into operative contact with the thermal equilibration area when the measurement layer is placed in operative association with the merging layer. The nanocalorimeter is configured to have the merging layer and the measurement layer non-integrated, making the measurement layer reusable.

Nanocalorimeter based on thermal probes

A temperature probe includes a substrate, a cantilever body portion formed on the substrate, having an anchor portion held in contact to the substrate and a free end portion extending out of the surface of the substrate, and a sputter-deposited thermistor sensor portion located at the free end portion of the cantilever body portion.

Vanadium oxide thermal microprobes

Thermal sensing devices can include two subsets of thermal sensors connected in a bridge by circuitry on the same support layer or surface with the sensors. Each thermal sensor can be formed in a patterned layer of semiconductor material, and the bridge circuitry can include leads formed in a patterned layer of conductive material, over or under the semiconductor layer. In one implementation, the bridge circuitry includes conductive portions that extend across and electrically contact the lower surface of each sensor's semiconductor slab. The bridge circuitry can also include pads that can be electrically contacted, such as by pogo pins. The device's reaction surface can be spaced apart from or over the thermal sensors. The device's components can be shaped and positioned so that the bridge's offset voltage is below the sensitivity level required for an application, such as by left-right symmetry about an axis.

Thermal sensing with bridge circuitry

A passive electronic device includes layers of a layered structure on a support surface. The device can include a first layer part that includes electrically conductive or semiconductive material and that has a contact surface. The device can also include second layer parts that include electrically conductive material and are in electrical contact with the contact surface, with a subset electrically connectible to external circuitry. At least one of the parts of the two layers can be produced by a printing operation or can include a printed patterned artifact such as an uneven boundary or an alignment. The printing operation can be direct printing or printing of a mask for etching or liftoff or both. The device could, for example, be a resistive device, such as a device with resistance varying in response to non-electrical stimuli, or a conductive device, such as with a contact pad for a pogo pin.

Passive electronic devices

A layered structure is produced on a support structure's surface. The layered structure can include a component that responds electrically to thermal signals, such as a thermistor, and can also include a layer part that has a printed patterned artifact such as an uneven boundary or an alignment. A layered structure can be produced by depositing a layer of material, printing a mask, and removing the exposed part of the layer.

Producing layered structures using printing

Thermal sensors for calorimetry can include vanadium oxide, heavily p-doped amorphous silicon, or other materials with high temperature coefficients of resistivity. Such thermal sensors can have low noise equivalent temperature difference (NETD). For example, a thermal sensor with NETD no greater than 100 &#x3bc;K over a bandwidth range of approximately 3 Hz or more can include a thermistor including vanadium oxide sputtered at room temperature under conditions that yield primarily VO; more specifically, the NETD can be no greater than 35 &#x3bc;K, or even 10 &#x3bc;K over a bandwidth range of approximately 3 Hz or more. If a low noise thermal sensor has NETD no greater than 50 &#x3bc;K over such a bandwidth range, a low noise output circuitry connected to its thermistor can provide an electrical output signal that includes information about input thermal signal peaks with amplitude of approximately 100 &#x3bc;K.

Resistive thermal sensing

In thermal sensing devices, such as for calorimetry, a support layer or central layer can have a thermometer element or other thermal sensor on one side and a thermally conductive structure or component on the other. The thermally conductive structure can conduct temperature or other thermal input signals laterally across the support layer or central layer. The temperature or signals can then be provided to the thermometer element, such as by thermal contact through the support layer. An electrically conducting, thermally isolating anti-coupling layer, such as of gold or chromium, can reduce capacitive coupling between the thermally conductive structure and the thermometer element or other thermal sensor.

Growing community of inventors

Los Altos, CA, United States of America

Michal V Wolkin