A circuitized structure with a 3-dimensional configuration. A base structure is provided that includes an insulating substrate of electrically insulating material with a flat configuration, and further includes an electric circuit including at least one layer of electrically conductive material arranged on the insulating substrate. The insulating material includes a thermosetting material being partially cured by stopping a cure thereof at a B-stage before reaching a gel point. The base structure is formed according to the 3-dimensional configuration, and the cure of the thermosetting material is completed.

Circuitized structure with 3-dimensional configuration

A device (10) for fatigue testing of materials comprises a frame (14), first and second clamping means (16,18) for holding a specimen (12) to be tested. First and second mounting means (20,22) mount the clamping means (16,18) on the frame (14). The mounting means (20,22) vibrationally isolate the clamping means (16,18) from the frame (14). Actuator means (24) moves the first clamping means (16) relative to the second clamping means (18) to apply a low cycle load on the specimen (12). Electrical insulating means (30) electrically insulate the frame (14) from the specimen (12). A shaker (26) is coupled to the second clamping means (18) to apply a high cycle load on the specimen (12). A detector (32) detects the vibration of the specimen (12) and sends an electrical signal to a control unit (42) which determines the resonant frequency of the specimen (12). The control unit (42) sends a signal to the shaker (26) to maintain the high cycle load at the resonant frequency of the specimen (12). Electrical potential drop probes (38) are provided on the specimen (12) to send a second electrical signal to the control unit (42) which is arranged to determine the rate of crack growth, the fatigue life to crack initiation and fatigue life to failure of the specimen (12).

Device and method for fatigue testing of materials

In one embodiment, a thermal conductivity detector in a gas chromatograph is provided with a sensor connected in a resistive bridge with an alternating voltage applied to the bridge. Changes in thermal conductivity of a gas in the sensor cause changes in the temperature and resistance of the sensor which unbalances the bridge. A component of the voltage difference caused by the imbalance varies as the third harmonic of the applied voltage and has a magnitude related to the thermal conductivity of the gas. This third harmonic is measured to determine the thermal conductivity of the gas. In another embodiment, a sensor in a cavity through which gas flows is alternately operated at two different temperatures, and a difference in power required for operation is measured. The difference is independent of the temperature of the cavity walls and proportional to the thermal conductivity. This difference is measured to determine the thermal conductivity of the gas.

Thermal conductivity detector

A technique for observing optical second harmonic generation effect at a surface of a material during processing thereof, particularly in the presence of a plasma, for controlling the processing of the material. A preferred form of the apparatus and method includes a combination of spectral, spatial, polarization and temporal filtering to allow observation of optical second harmonic generation and control of processing of the material with processes such as reactive ion etching to a high degree of resolution.

Detection of interfaces with atomic resolution during material processing by optical second harmonic generation

Frequency domain reflectometer and method of locating faults in a transmission line utilized by the reflectometer are disclosed. The reflectometer suppresses harmonics that may be interpreted as faults that in actuality do not exist. In general, the reflectometer applies a sweep signal to the transmission line in order to obtain a reflected sweep response signal. Then, the reflectometer obtains a sweep response spectrum from the reflected sweep response signal. The reflected sweep response signal includes a plurality of spectral peaks which represent the frequency components of the reflected sweep response signal. Then, the reflectometer mathematically determines which spectral peaks of the reflected sweep response spectrum were generated due to harmonics in the reflected sweep response signal. After determining that a spectral peak is a harmonic of a fundamental spectral peak, the reflectometer subtracts a percentage of the fundamental spectral peak from the harmonic spectral peak, thereby suppressing a harmonic of the reflected sweep response signal. The reflectometer then obtains from the adjusted sweep response spectrum a location of an impedance mismatch in the transmission line.

Frequency domain reflectometer and method of suppressing harmonics

The tester and method for nondestructively detecting nonlinearity faults in conductors includes the application of a composite AC and DC drive signal to the device under test in such manner that nonlinearities in the device under test produce fault signals including second harmonics, due to local changes of resistance caused by ohmic heating. Electronic filters are used to select out and amplify the second harmonic only, eliminating the direct current and fundamental frequency components of the initial test pulse, plus third and subsequent harmonics. The filtered second harmonic signals from the device under test are then phase-compared to a phase-shifted second harmonic signal produced by a frequency doubler from the test signal generator oscillator to cancel out the second harmonic signals from the good conductor; the remaining phase anomaly signals control a threshold detector remaining to provide fault indication.

Nonlinearity detection using fault-generated second harmonic

The Figure shows a system for non-destructive detection of current restricting defects, such as cracks, narrowing, intermittent opens etc, in a conductor, e.g. a printed conductor. A composite test signal is applied to the test conductor 3 via probes 1 and 2. The signal is produced by a generator circuit 4 comprising a frequency (f o ) oscillator 5, amplifier 6 and D.C. source 7. The defects in the conductor 3 cause its resistance to vary at the same frequency as the oscillator signal and cause current variations through the conductor. The signal at node 4A comprises a component Vf o at frequency f o , a component 2f o GV at twice the frequency f o due to the resistive variation of the restricting defect and a component 2f o CV at two the frequency f o due to the resistance heating of the whole conductor. The f o component is rejected by filter 8 and the 2f o components amplified (9) and filtered by band pass filter 10. The amplified filtered signal is supplied as one input to a phase detector 12, the other input being derived from node 48, frequency doubler 14, band pass filter 15 and phase shifter 16. The detector 12 operates as a phase, sensitive demodulator to suppress the 2f o CV component and to compare the phase of the 2f o GV component with the 2f o component from phase shifter 16. The result of the comparison is manifested as a DC voltage which is logarithmically amplified and applied to indicator meter 18 and, via threshold detector 19, to defect indicator 20.

Stefano Thomas Herman Di

Papers

Nonlinearity detection using fault-generated second harmonic

Apparatus for and method of testing the conductive properties of a conductor