Abstract: A layer of dopant is implanted in the passivation of a semiconductor die to facilitate testing of the die by a scanning electron microscope voltage contrast system. The layer of dopant is capacitively coupled to circuits under the passivation and is coupled to ground to allow charge to bleed to ground through a high resistivity path. The resistivity is low enough to allow E-beam charge bleed off, but not bleed off of higher frequency capacitive coupled signals. The disclosure is also applicable to photo generated electron voltage contrast.

Abstract: An electrical power source or power cell (10) includes a semiconductor material (12) having an N region (14), a P region (16) and a P-N junction (18). A radioactive source (24) associates with P-N junction (18) and emits energy or radioactive particles (26) into semiconductor material (12). In semiconductor material (12), electron-hole pairs are formed in N region (14) and P region (16) to cause electrical current to pass through P-N junction (18) and produce, therefrom, electrical power.

Abstract: A system (10) is provided for approximating a nonlinear function. The system (10) comprises first and second multiple generating circuits (12) and (14) for multiplying a first quantity and a second quantity by up to three integer powers of two. First and second function generating circuits (16) and (18) generate first and second functions of the first and the second quantities by combining the multiples generated in first and second multiple generating circuits (12) and (14). First and second approximation generating circuits (20) and (22) generate first and second approximations of the nonlinear function by shifting the output of first and second function generating circuits (16) and (18). Approximation selecting circuit (24) outputs the appropriate approximation generated in first and second approximation generating circuits (20) and (22).

Abstract: A method and apparatus for measuring submicron linewidths, using diffraction gratings. A set of "fixed-linewidth variable-pitchwidth" test gratings has a number of gratings, each grating having the same linewidth but having different pitchwidths. These gratings are illuminated to form diffraction patterns. A set of peak intensities of the first or second order diffraction image from each grating is recorded. Either of these intensity values forms a curve around an extrema, which represents the intensity from a grating whose pitchwidth is equal to one-half the linewidth.

Abstract: An electron beam imaging system (10) includes a photoemitter plate (12). An optical image beam (15) is directed through a pattern mask (18), which is imaged onto the photoemitter (12). The photoemitter (12) emits electrons from those unmasked regions illuminated by the optical image beam, emitting an extended-source electron beam that carries the mask image. The extended-source electron beam is focused (34) onto a device under fabrication (40), providing a single-stage electron lithographic patterning function. The optical source (16) is chosen so that optical image beam energy is nearly identical to the work function for the photoemissive coating (14) of the photoemitter (12). As a result, the photoemitter (12) emits electrons with substantially zero kinetic energy, allowing the emitted electrons to be accelerated through the electron beam focusing elements (34) with very nearly identical electron velocities, thereby minimizing chromatic aberrations.

Abstract: An apparatus and method for testing an integrated circuit (12) generally comprises an input pad (14) and output pad (15) having photo-sensitive sensors (20, 46) formed thereon for eliminating the need to come into direct contact with a probe card for testing the integrity of an integrated circuit.

Abstract: A scanning electron microscope (28) is connected to a test structure (48) formed on a semiconductor wafer. The test structure (48) comprises a plurality of first parallel structures (54) and a plurality of second parallel structure (56) transverse to and interlocking with the first structures (54). An island (60) is formed within a grid (58) formed by the structures (54-56) and is separated therefrom. An electron beam (38) from the scanning electron microscope (28) is aimed at the structure (48) and secondary electrons emitted therefrom are visually displayed on a monitor (44). The visual display (47) provides information on whether the island (60) is electrically separated from the mesh (58) or shorted thereto by comparing the intensity of the various islands (60).

Abstract: An electron beam imaging system (10) includes a photoemitter plate (12). An optical image beam (15) is directed through a pattern mask (18), which is imaged onto the photoemitter (12). The photoemitter (12) emits electrons from those unmasked regions illuminated by the optical image beam, emitting an extended-source electron beam that carries the mask image. The extended-source electron beam is focused (34) onto a device under fabrication (40), providing a single-stage electron lithographic patterning function. The optical source (16) is chosen so that the optical image beam energy is nearly identical to the work function for the photoemissive coating (14) of the photoemitter (12). As a result, the photoemitter (12) emits electrons with substantially zero kinetic energy, allowing the emitted electrons to be accelerated through the electron beam focusing elements (34) with very nearly identical electron velocities, thereby minimizing chromatic aberrations.

Abstract: A disposable integrated circuit test head (34) communicates a plurality of test signals between test nodes (20) of an integrated circuit and test circuitry. Disposable high-density test head (30) comprises signal platform (24) which includes tape layer (24) and interconnection lines (28). Interconnection lines (28) include signal leads (30) and bumps (32). Interconnection lines (28) coupled with test nodes (20) to electrically connect test nodes (20) with the test circuitry and communicate test signals between test nodes (20) and the test circuitry. Pusher block (36) engages signal platform (24) at tape layer (26) opposite interconnection lines (28) and applies force through tape layer (24) to interconnection lines (28). This allows positive engagement of interconnection lines (28) with test nodes (20). Pusher block (36) comprises rigid force applying plate (38) which adheres to compliant layer (40) at junction (42).

Abstract: A system and method for testing the continuity of interconnecting nets on a substrate to be used in multi-chip technology is provided. The system includes coupling a test pad (15) to the net (12) to be tested. The test pad (15) is coupled through a diode (34) to a common node (32). The voltage of a first node (16) of the net (12) is sensed by a voltmeter (38) which is coupled to ground. A predetermined current signal is applied to each node (16, 18, 20, 22) in the net through the use of a probe (42). The voltage of the remaining nets (14) is sensed by a voltmeter (44). If an erroneous interconnection (31) is present between the net (12) to be tested and any other net (14) on the substrate, the voltage of the other net (14) will fluctuate. The voltmeter (38) will indicate if there is an electrical connection between the node (16) and the test pad (15) during testing.

Abstract: A scanning electron microscope (SEM) (24), or other irradiating device, is used to create a potential in sample areas (39b) of a test structure (39) formed on the surface of an integrated circuit wafer. A conduction path between the irradiated sample area and a common area (39a) is detected via an ammeter (40) connected between the sample area (39b) and a voltage source (42). Monitoring circuit (44) produces an output indicative of those sample areas (39b) which are electrically coupled to the common area (39a).

Abstract: A scanning electron microscope (28) is connected to a test structure (48) formed on a semiconductor wafer. The test structure (48) comprises a plurality of first parallel structures (54) and a plurality of second parallel structure (56) transverse to and interlocking with the first structures (54). An island (60) is formed within a grid (58) formed by the structures (54-56) and is separated therefrom. An electron beam (38) from the scanning electron microscope (28) is aimed at the structure (48) and secondary electrons emitted therefrom are visually displayed on a monitor (44). The visual display (47) provides information on whether the island (60) is electrically separated from the mesh (58) or shorted thereto by comparing the intensity of the various islands (60).