Ultra small magnetic field sensors are created using magneto-optic slab waveguides coupled to optical fiber. The
magneto-optic material used is bismuth-doped rare earth iron garnet (Bi:RIG). By etching close to the core of D-type
optical fiber and attaching a magneto-optic material, light transfers from the fiber to the slab waveguide at specific
wavelengths. The wavelengths that couple depend on the refractive index of the slab that changes in the presence of a
magnetic field. When a field is applied, the wavelength coupling shifts and a resulting change in power can be detected.
The sensors reported in this paper detect magnetic fields as low as 11 A/m.
Modern electronics are often shielded with metallic packaging to protect them from harmful electromagnetic
radiation. In order to determine the effectiveness of the electronic shielding, there is a need to perform non-intrusive
measurements of the electric field within the shielding. The requirement to be non-intrusive requires
the sensor to be all dielectric and the sensing area needs to be very small. The non-intrusive sensor is attained
by coupling a slab of non-linear optical material to the surface of a D shaped optical fiber and is called a slab
coupled optical fiber sensor (SCOS). The sensitivity of the SCOS is increased by using an organic electro-optic
We present progress on advanced optical antennas, which are compact, small size-weight-power units capable
to receive super wideband radiated RF signals from 30 MHz to over 3 GHz. Based on electro-optical
modulation of fiber-coupled guided wave light, these dielectric E-field sensors exhibit dipole-like azimuthal
omni directionality, and combine small size (<< λRF) with uniform field sensitivity over wide RF received
signal bandwidth. The challenge of high sensitivity is addressed by combining high dynamic range photonic
link techniques, multiple parallel sensor channels, and high EO sensing materials. The antenna system
photonic link consists of a 1550 nm PM fiber-pigtailed laser, a specialized optical modulator antenna in
channel waveguide format, a wideband photoreceiver, and optical phase stabilizing components. The optical
modulator antenna design employs a dielectric (no electrode) Mach-Zehnder interferometer (MZI) arranged
so that sensing RF bandwidth is not limited by optical transit time effects, and MZI phase drift is bias
stabilized. For a prototype optical antenna system that is < 100 in3, < 10 W, < 5 lbs, we present test data on
sensitivity (< 20 mV/m-Hz1/2), RF bandwidth, and antenna directionality, and show good agreement with
This paper presents a means for creating optical fiber sensors that are capable of detecting electric fields. This
novel E-field sensor is formed as part of a contiguous fiber resulting in a flexible and small cross-section device
that could be embedded into electronic circuitry. The sensor is formed by partially etching out the core of a
D-shaped optical fiber and depositing an electro-optic polymer. Using PMMA and DR1 for proof of concept,
we demonstrate the operation of the first in-fiber hybrid waveguide electric field sensor with a sensitivity of less
than 100 V/m at a frequency of 2.9 GHz. Sensors optimized for low loss (~1dB) have an estimated E&pgr; of 222
MV/m. A sensor with an E&pgr; of 60 MV/m is also demonstrated with an insertion loss of 14.4 dB.
Based on the electro-optic (EO) polymer Mach–Zehnder interferometer (MZI) technology, IPITEK develops optical E-field sensor devices. As a receive antenna, the present device exhibits wide and flat bandwidth, up to 10 GHz. Testing the E-field sensor response was performed using a transverse electromagnetic (TEM) cell at frequencies from 0.2 to 1 GHz, and a set of 4 horn antennas at frequencies from 2.6 to 12 GHz. The minimum detectable E-field, Emin, was about 70 mV/(m) for an all-dielectric field sensor and was about 7 mV/(m) for a sensor with electrodes and a short wire loop antenna. A photonic down-conversion technique was developed to address bandwidth and receiving power limitations of the receiver photodetector. The down-conversion experimental results agree well with the theoretical heterodyne predictions. The EO polymer sensor sensitivity can be further improved by reducing the device optical insertion loss, optimizing the photodetector and detection circuitry, and using recently developed higher EO coefficients polymers.
Aimed at test and evaluation needs on high power microwave (HPM) weapons, we describe new developments on miniature all-dielectric optical field sensors with flat RF sensing response from ~ MHz to 12 GHz, with negligible field perturbation, good sensitivity (~70 mV/(mH√z), and >100dB dynamic range. Present devices use a 20 mm long sensing region in an integrated optical (IO) waveguide Mach-Zehnder interferometer (MZI) using electrooptic (EO) polymer for the waveguide. The fiber-coupled optical transmitter/receiver utilizes common optical communication technology. The incident HPM RF field induces an instantaneous change in the index of refractive of the polymer that is converted into an optical intensity modulation in the MZI device. The poled EO polymer requires no electrodes nor metallic antennas that can distort the field under test. We characterized the frequency response and polarization sensitivity of the field sensor, and both agree well with modeling predictions. Common fabrication limitations result in devices with sensitivity to thermal drift. New sensor designs are being developed with remote bias control that also can provide self-calibration. To further reduce the sensor size and insertion loss, beneficial for array applications, an "in-fiber" field sensor is being developed. The core of a D-shaped fiber is partially removed and replaced with EO polymer. Such a device may use polarization modulation sensing, or be configured in similar MZI structures as the IO waveguide sensors.
Collimated laser-Plasma Lithography (CPL) offers potential to match Next Generation Lithography (NGL) needs, ending a pursuit of ever-larger lens NA and ever-smaller k1 process resolution factor. Powered by a laser-produced plasma (LPP) source at 1nm, it capitalizes on mature development of x-ray lithography, which is the only NGL that has produced working chips. JMAR is upgrading its CPL system to increase overall throughput (system power) and is focusing on solving a known industry problem for which CPL presents an advantage: printing sub-90nm contacts in memory chips.
The paper will discuss CPL system characteristics and performance. Supporting information on the upgrades to the laser and x-ray generator will be included. Specific resists and mask techniques and the roadmap leading to multi-generational support capability down to the 45nm node will be described.
JMAR develops Laser-Produced Plasma (LPP) sources for lithography applications, and has specifically developed Collimated laser-Plasma Lithography (CPL) as a 1 nm collimated point source and stepper system to address sub-100nm lithography needs. We describe the CPL source development, show demonstrated sub-100nm printing capability, and describe status of a beta lithography tool. The system will be power-scaled to address silicon device contacts and vias at 90nm and below. This development has much in common with LPP Extreme UltraViolet Lithography (EUVL) sources; an EUV source concept is presented to address the high power requirements of that Next Generation Lithography (NGL).
In the world of micro- Lithography, several options exist for obtaining features below the 100nm level. Options include a variety of methods which range from additional process steps in etch, multilayer resist systems, or expensive throughput limited direct write E-beam systems. Each comes with a handful of trade offs in uniformity, repeatability and cost. Collimated (LASER) Plasma Lithography (CPL), on the other hand offers a full field exposure with minimal process intervention to obtain resolution below the 100nm barrier. CPL, uses a membrane 1x proximity mask and a collimated light source with energy peaking at 11 A°. By using a mask, an entire 22mm x 22mm field (30mm x 30mm with the next generation) can be exposed at once regardless of chip density, removing any throughput concerns as well as placement, stitching and typical E-beam machine flaw defects. Collimation, provides a predictable flux of energy to ensure minimal global divergence and energy level variation. Energy at 11 A°, allows for a high level of uniformity and penetration within the resist, without introducing resolution compromising scattering or standing wave effects.
This Paper will demonstrate the capabilities of CPL as well as the advantages over traditional lithography in obtaining features below 100nm. We will also depict process techniques which take full advantage of improvements in CAR, and experiments which suggest reduction possibilities through variables in mask fabrication.
X-ray spectra of Cu plasmas at the focus of a four-beam, solid-state diode-pumped laser have been recorded. This laser-plasma X-ray source is being developed for JMAR's lithography systems aimed at high- performance semiconductor integrated circuits. The unique simultaneous overlay of the four sub-nanosecond laser beams at 300 Hertz produces a bright, point-plasma X-ray source. PIN diode measurements of the X-ray output indicate that the conversion efficiency (ratio of X-ray emission energy into 2π steradians to incident laser energy) was approximately 9 percent with average X-ray power yields of greater than 10 Watts. Spectra were recorded on calibrated Kodak DEF film in a curved-crystal spectrograph. A KAP crystal (2d = 26.6 Angstroms) was used to disperse the 900 eV to 3000 eV spectral energies onto the film. Preliminary examination of the films indicated the existence of Cu and Cu XX ionization states. Additional spectra as a function of laser input power were also recorded to investigate potential changes in X-ray yields. These
films are currently being analyzed. The analysis of the spectra provide absolute line and continuum intensities, and total X-ray output in the measured spectral range.
A compact x-ray source radiates 24 Watts average power of 1nm x-rays in 2 (pi) steradians. The laser produced plasma x-ray source has a 300 W laser driver which is a compact, diode-pumped solid-state Nd:YAG laser system. The x-ray conversion efficiency is 9 percent of the laser power delivered on target. The x-ray source was used to demonstrate x-ray lithography of 75 nm lines. The x-ray source is optimized for integration with a x-ray stepper to provide a complete x-ray lithography exposure tool for the manufacture of high-speed GaAs devices.
A compact laser produced plasma x-ray source radiates 24 Watts average power of 1nm x-rays in 2(pi) steradians. The x-ray power conversion efficiency is 9% from the laser average power focused on the x-ray target. The laser-plasma x-ray source is generated by a 300W compact, diode-pumped, solid-state Nd:YAG laser system. The tabletop laser system is constructed on a 4ft x 8ft optical bench and the laser modules are 1ft high. The total wall-plug power consumption for this laser-produced-plasma x-ray source is 22 kW. The x-ray source is optimized for integration with and x-ray stepper to provide a complete x-ray lithography exposure tool for the manufacture of high speed GaAs devices.
A high power picosecond soft x-ray source is generated by a compact, modular, diode pumped solid state laser BriteLightTM. Three x-ray source version are constructed from laser modules with increasing power. The power of the x-ray sources is tailored to potential applications. The building block of such a modular system is a 3 Watt x-ray power source with 1.1 keV x-ray photon energy. The laser system is very compact with dimensions of 4 ft X 3 ft X 1 fit. It is composed of a laser master oscillator, pre-amplifier and one power amplifier. A four laser amplifier system was also constructed in order to generate 12 W of x-rays for application to x-ray lithography.
An x-ray power of 2.8 Watts at the 1 nm x-ray lithography wavelength was generated by a copper plasma formed by a single laser beam focused to an intensity of greater than 1014 W/cm2 on a copper tape target. The all solid state BritelightTM YAG laser has 700 ps pulse duration, 300 Hz pulse repetition rate, average power of 75 Watts, and less than 2 times diffraction limited beam quality at the fundamental 1.064 micrometer wavelength. The single beam laser system has a master oscillator, a preamplifier and one power amplifier, all diode pumped. Measurements confirmed negligible copper vapor debris at 8 cm from the laser-plasma source with atmospheric pressure He gas and modest gas flow. The point source x-ray radiation was collimated with either a polycapillary or grazing mirror collimator. The near-parallel beam of x-rays has good divergence both globally (0.5 mrad) and locally (less than 3 mrad), good uniformity (2% achievable goal) and large uniform field size (20 mm X 20 mm full field and 25 mm X 36 mm scanning system). High-resolution lithography was performed for the first time with collimated 1 nm point source x-rays. A power scaling system is being built with eight amplified beams in parallel on the x-ray target, and is expected to achieve 24 - 30 Watts of x-rays. A 16 beam laser plasma x-ray lithography system could achieve a throughput of 24 wafer levels per hour using 300 mm diameter wafers.
The speed demands that determine the frame rate requirements for dynamic infrared scene projectors are discussed together with the speed characteristics and limitations of the scene projectors currently being developed. Multiplexing/addressing scheme limitations are discussed and specific infrared projection technologies are surveyed with particular attention given to the design compromises that tend to determine speed capability.
This paper reviews recent development and application of the infrared version of the liquid crystal light valve (LCLV). We describe delivered IR image projectors for advanced end-to- end laboratory testing of IR seeker and sensor systems. System performance characteristics are given. A newly developed version of the device has much higher contrast with low IR background image capability.
The authors report the operation of the Hughes Schottky diode-based silicon liquid crystal light valve (SLV) using readout light in the visible region. Limiting resolutions of 28 lp/mm limited by the Schottky diode periodicity, contrast ratios of >100:1, visible input light sensitivities of better than 50 (mu) W/cm2, and response times as fast as 5 ms have been measured. Both standard twisted nematic and homeotropically-aligned liquid crystal configurations have been utilized. The main parameter of this device is the leakage current of the Schottky diodes.