摘要:
A data recording and reproducing apparatus is disclosed in which an optical disc for recording, reproducing or erasing data is radiated with an erasing light beam and a recording-reproducing light beam sequentially to record or reproduce the data with the recording-reproducing light beam and erase the data with the erasing light beam. In rewriting the data, the erasing light beam is radiated in advance of the recording-reproducing light beam on a data section of the disc, and the old data is erased by temperature increase and annealing by the erasing light beam, while new data is recorded by temperature increase and quenching with the recording-reproducing light beam set to the recording light intensity. After recording the new data, the light intensity of the erasing light beam is gradually decreased and turned off. In rewriting the sector data, the erasing light beam is radiated on the data section in advance of the recording-reproducing light beam, and by the temperature increase and annealing with the erasing light beam, the old data is erased, while new data is recorded by temperature increase and quenching with the recording-reproducing light beam set to the recording light intensity. After recording the new data, the light intensity of the erasing light beam is turned off after being modulated for a predetermined time. By doing so, the process of the temperature and quenching is eliminated which otherwise might be required at the time of turning off the erasing light beam, thereby preventing occurrence of a recording trace and a defect of the recording medium by a thermal shock.
摘要:
An information recording and reproducing apparatus for recording and reproducing information on and from a disk type information recording medium, wherein the information recording medium is used in which normal sectors (S1, Sn) each having an address formatted on an address area 12 in a sector ID field 9 and an alternative sector R1 having an address not yet recorded thereon are included on a same track. When a defective sector S3 is detected, first, the address of the defective sector is disabled to be reproduced by recording a delete signal 109 on the address area 12 of the defective sector S3, and at the same time, the address of the defective sector is recorded on an address area 13 in the unused alternative sector R1 located on the same track as the defective sector S3, and then, the data to be recorded on the defective sector is recorded within the alternative sector R1. Owing to such an operation for using an alternative sector, the alternative sector having the same address and data as the defective sector is formed on the same track as the defective sector. As a result, an information recording and reproducing apparatus which enables to access the alternative sector without an additional seek operation at the time of reproduction is provided.
摘要:
In an information and recording and reproducing apparatus using a disc-shaped information recording medium having a plurality of recording tracks, each of which recording tracks is divided into a plurality of sectors, to record and reproduce information on and from the information recording medium on a sector-by-sector basis, when a target sector is detected to be a defective sector whose address can not be reproduced, in the first place, a reference sector, which is positioned preceding the defective target sector and whose address can be reproduced, is detected. Then, a rotational latency time from the detected reference sector to the defective target sector is measured by using:a time measuring circuit for measuring the rotational latency time per se; ora counter circuit for counting the number of a sector mark or sector marks which indicate the presence of an associated sector or sectors and which are detected during the rotational latency time,so that the defective target sector may be taken to be a normally detected target sector whereby information may be recorded and reproduced on and from the defective target sector, thereby making it possible to perform recording and reproduction of information on and from a defective sector whose address can not be reproduced.
摘要:
In an optical disk system of the type including an optical disk for performing the recording and reproduction of data by use of a semiconductor laser and an optical disk recording and reproducing apparatus, an optical disk, optical disk recording and reproducing apparatus and copy preventive method for optical disks capable of preventing copying of the stored data from one optical disk on another. Irrespective of the kinds of optical disks, such as, read only-type optical disk, DRAW-type optical disk and erasable optical disk, each of the optical disks is provided in common with sectors from which data can be reproduced but not recorded on, i.e., data record-protected sectors and at least part of the stored data is stored in the record-protected sectors of the optical disk, thereby protecting the stored data from being recorded on the same address sectors of another recordable optical disk forming a part of the optical disk system.
摘要:
An information recording and reproducing apparatus for recording and reproducing information on and from a disk type information recording medium, wherein the information recording medium is used in which normal sectors (s1, Sn) each having an address formatted on an address area 12 in a sector ID field 9 and an alternative sector R1 having an address not yet recorded thereon are included on a same track. When a defective sector S3 is detected, first, the address of the defective sector is disabled to be reproduced by recording a delete signal 109 on the address area 12 of the defective sector S3, and at the same time, the address of the defective sector is recorded on an address area 13 in the unused alternative sector R1 located on the same track as the defective sector S3, and then, the data to be recorded on the defective sector is recorded within the alternative sector R1. Owing to such an operation for using an alternative sector, the alternative sector having the same address and data as the defective sector is formed on the same track as the defective sector. As a result, an information recording and reproducing apparatus which enables to access the alternative sector without an additional seek operation at the time of reproduction is provided.
摘要:
An information recording and reproducing apparatus records and reproduces information on and from an optical recording disk having a sector recording format of frame structure in which data in each sector are divided into a plurality of frames, and a data head identification mark is affixed to the head of each of the frames, so as to prevent propagation of a demodulation error due to failure of word synchronization attributable to pull-out of a PLL during data reproduction. In the apparatus, one frame pulse is generated for each of the frames on the basis of a sector identifier detection signal and a frame data demodulation start signal, and, according to the result of counting the frame pulses, the frame numbers of frame data demodulated and stored in a sector buffer memory are accurately detected. The frame pulse is generated on the basis of the sector identifier detection signal until the data head identification signal is first detected, and, once the data head identification signal is detected, the frame pulse is generated on the basis of the data demodulation start signal. Therefore, even if the data head identification signal of a frame cannot be detected resulting in dropout of data in that frame, the succeeding frame data can be stored at the assigned addresses in the sector buffer memory.
摘要:
An information recording and reproducing apparatus records and reproduces information in and from a recording medium including an information recording region divided into a plurality of sectors. In recording and reproducing information in and from the recording medium, each sector includes a sector address part formatted and a data recording part for recording data. A predetermined signal is overwritten in the address of a sector thereby making reproduction of the address impossible to prevent data from being recorded again by error in the sector containing data, while at the same time protecting the writing in the sectors. In data recording, on the other hand, the address signal from the recording medium is binary-coded at a different level to detect a sector of unstable address reproduction, so that a predetermined signal is overwritten in the address of this sector to make subsequent reproduction of the address impossible, thus permitting recording only in the sectors of stable address reproduction for stable data reproduction. Further, an optical disc having sectors of stable address reproduction alone detects a sector of unstable reproduction at the time of inspection, and overwrites a predetermined signal in the address part of the particular sector to make subsequent reproduction of the address impossible.
摘要:
The present invention relates to high-speed acquisition of both a perpendicular observation image and a tilt observation image, in observation using a scanning electron microscope. An electron-beam observation apparatus includes: a first electro-optical system which scans a converged electron beam from a substantially perpendicular direction to a defect on a target wafer to be observed, and acquires a defect image signal with perpendicular observation by detecting a secondary electron image or a reflected electron image generated from the defect; and a second electro-optical system which scans a converged electron beam from a tilt direction to the defect, and acquires a defect image signal with tilt observation by detecting a secondary electron image or a reflected electron image generated from the defect.
摘要:
Size characteristic quantities are measured at a plural locations. The size characteristic quantities include edge widths, pattern widths, and/or pattern lengths of the electron-beam images of a resist-dropout pattern and a resist-remaining pattern that are located such that the effective exposure quantities differ depending on the places. With the predetermined measurement errors added thereto, the size characteristic quantities are compared with model data that has been created in advance and that causes various exposure conditions to be related with the size characteristic quantities measured under these various exposure conditions. This comparison makes it possible not only to estimate deviation quantities in the exposure quantity and the focal-point position from the correct values, but also to calculate ambiguity degrees of the estimated values. This, allows the implementation of a proper monitoring/controlling of the exposure-condition variations (i.e., the deviations in the exposure quantity and the focal-point position) in the lithography process.
摘要:
A hotspot searching apparatus manufactures a small number of chips or regions on a semiconductor wafer under respectively different manufacturing process conditions, compares SEM images of their external appearances to output a point having large differences as a narrow process window, that is, a process monitoring point that should be managed in mass production, the narrow process window having a narrow manufacturing process condition (exposure condition) in the manufacturing of the semiconductor wafer, and sets the point as a measurement point by a CD-SEM apparatus, such that it extracts and determines plural circuit pattern parts having a narrow manufacturing process margin as the process monitoring point in a short time and a process monitoring point monitoring performs shape inspection or shape length measurement in detail at high resolution.