• Journal of the Korean Institute of Telematics and Electronics A
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• v.31A no.12
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• pp.80-90
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• 1994

To develop VLSI of higher packing density with 0.5.mu.m gate length of less, semiconductor devices require shallow junction with higher doping concentration. the most common method to form the shallow junction is ion implantation, but in order to remove the implantation induced defect and activate the implanted impurities electrically, ion-implanted Si should be annealed at high temperature. In this annealing, impurities are diffused out and redistributed, creating deep PN junction. These make it more difficult to form the shallow junction. Accordingly, to miimize impurity redistribution, the thermal-budget should be kept minimum, that is. RTA needs to be used. This paper reports results of the diffusion characteristics of PSG film by varying Phosphorus weitht %/ Times and temperatures of RTA. From the SIMS.ASR.4-point probe analysis, it was found that low sheet resistance below 100 .OMEGA./ㅁand shallow junction depths below 0.2.mu.m can be obtained and the surface concentrations are measured by SIMS analysis was shown to range from 2.5*10$^{17}$ aroms/cm$^{3}$~3*10$^{20}$ aroms/cm$^{3}$. By depending on the RTA process of PSG film on Si, LDD-structured nMOSFET was fabricated. The junction depths andthe concentration of n-region were about 0.06.mu.m. 2.5*10$^{17}$ atom/cm$^{-3}$ , 4*10$^{17}$ atoms/cm$^{-3}$ and 8*10$^{17}$ atoms/cm$^{3}$, respectively. As for the electrical characteristics of nMOS with phosphorus junction for n- region formed by RTA, it was found that the characteristics of device were improved. It was shown that the results were mainly due to the reduction of electric field which decreases hot carriers.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.15 no.1
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• pp.63-79
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• 1993

To repair bony defects with tansplanted bone in the body, fresh autogenous bone is undoubtly, the most effective bone graft for clinical applications. But the demineralized bone has the matrix-induced bone formation which was suggested by Urist in 1965. Many authors assisted that demineralized bone powder induces phenotypic conversion of mesenchymal cells into osteoblasts, with high-density bone formation. The process of inducing differentiated cells becomes osteogenic properties. The purpose of this study was to evaluate the osteoinductive capacity of allogenic freeze-dried demineralized bone block (FDD, $7{\times}7mm$) and to compare FDD with the same sue of deep-frozen allogenic bone(DF), fresh autogenous bone (A) after implantation. The histological and ultrastructural features of tissue responses were examined after 1, 2, 4, 6, 8 weeks implantation of each experimental groups in the operative site of the New Zealand white rabbits. The results were as follows : 1. Inflammatory cell infiltration generally has appeared at 1 week, but reduced at 4 weeks in each group, but most severe in DF group. 2. Osteoblastic activity has increased for 4 weeks, but decreased at 6 weeks in each group and there was no significant difference among experimental groups. 3. New bone formation has begun at 1week, least activations in A groups, and showed the revesal line of bone formation among each group at 6 to 8 weeks. 4. Bone resorption has appeared at 1 week, but disappeared at 4 weeks in both A and DF groups, but more severe in DF than A groups. 5. In ultrastructural changs, the DF group have showed the most remarkable osteoclastic activities among experimental groups. 6. Osteoid or tangled collagen fibrils near the implanted sites were replaced by more mature, lamellated bony trabeculae during bone remodeling. There was little difference among each experimental groups. 7. During the convertion osteoblasts to osteocytes which embedded within the bone matrix, there was organ-less-poor cytoplasm, increased nuclear chromatin, abundant rough endothelial reticulum (RER) in each groups. From the above the findings, the DF group shored more bone resorption and foreign body reaction than FDD and A groups, and FDD group showed more new bone formation or osteoblastic activity than DF and A groups in early stage. There was no significant difference of cellular activities among the FDD DF, and A groups according to the time.

• Journal of Yeungnam Medical Science
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• v.30 no.1
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• pp.31-35
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• 2013

Hematoma is quite a common complication of femoral arterial catheterization. However, to the best of our knowledge, there have been no previous studies regarding deep vein thrombosis (DVT) caused by compression of a vein due to a hematoma. We report a case of a hematoma developing after femoral arterial catheterization and causing extensive symptomatic DVT. A 59-year-old male was seen in our Emergency Department with right lower leg swelling 15 days after coronary stent implantation performed using right femoral artery access. Computed tomographic (CT) scanning revealed a large hematoma (45 mm in its longest diameter) compressing the common femoral vein and with DVT from the right external iliac vein to the popliteal vein. Due to the extensive DVT involvement, we decided to release the compressed common femoral vein by surgical evacuation of the large hematoma. However, even following evacuation of the hematoma, as the DVT did not resolve soon, further mechanical thrombectomy and catheter-directed thrombolysis were performed. Angiography then showed nearly resolved DVT, and the leg swelling was improved. The patient was discharged with the anticoagulation medication, warfarin.

• Proceedings of the Korean Vacuum Society Conference
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• 2012.02a
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• pp.314-314
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• 2012

The dilute magnetic semiconductors (DMS) have been developed to multi-functional electro-magnetic devices. Specially, the Si based DMS formed by ion implantation have strong advantages to improve magnetic properties because of the controllable effects of carrier concentration on ferromagnetism. In this study, we investigated the deep level states of Fe- and Co-ions implanted Si wafer during rapid thermal annealing (RTA) process. The p-type Si (100) wafers with hole concentration of $1{\times}10^{16}cm^{-3}$ were uniformly implanted by Fe and Co ions at a dose of $1{\times}10^{16}cm^{-2}$ with an energy of 60 keV. After RTA process at temperature ranges of $500{\sim}900^{\circ}C$ for 5 min in nitrogen ambient, the Au electrodes with thickness of 100 nm were deposited to fabricate a Schottky contact by thermal evaporator. The surface morphology, the crystal structure, and the defect state for Fe- and Co- ion implanted p-type Si wafers were investigated by an atomic force microscopy, a x-ray diffraction, and a deep level transient spectroscopy, respectively. Finally, we will discuss the physical relationship between the electrical properties and the variation of defect states for Fe- and Co-ions implanted Si wafer after RTA.

• Archives of Plastic Surgery
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• v.34 no.4
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• pp.508-511
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• 2007

Purpose: Dermoid cysts are almost always caused by congenital events. The most widely accepted pathogenesis is that the cysts are dysembryogenetic lesions that arise from ectodermic elements entrapped during the midline fusion. We report a rare case of dermoid cyst, which occurred not congenitally but newly in the subcutaneous scar tissue secondary to trauma. Methods: A 26-year-old man had a deep submental laceration caused by a car accident and got a primary wound closure 16 months ago. There were 18 cm-long submental hypertrophic scar and newly developed palpable masses inside the subcutaneous layer at the center of the scar. Initial impression was an epidermal cyst or a thyroglossal duct cyst. Ultrasonographic finding showed two cystic masses inside the scars at the submental area, but impressed dermoid cysts. The cystic masses were completely removed with W-plasty and histological examination were followed. Results: The histological diagnosis was dermoid cysts which were mainly composed of keratotic squamous epithelium in their inner surface linings and numerous skin appendages such as sebaceous glands, sweat glands, and hair follicles in their cystic lumens histopathologically. During the follow-up period of 25 months, there was no recurrence of any subcutaneous mass in the site of scar. Conclusion: We report a very unusual case of dermoid cysts developed by an acquired cause, considering that the accidental inclusion of deep skin elements caused by a trauma can be a critical origin of dermoid cysts.

• Journal of Korean Neurosurgical Society
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• v.67 no.2
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• pp.249-256
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• 2024

The Leksell frame-based transcerebellar approach was proposed with the arc support frame attached upside down to the Z coordinate. This study presented practical tips and considerations for obtaining adequate tissue samples for deep-seated cerebellar lesions or lower brainstem lesions specifically those accessible via the cerebellar peduncle. For practical insights, the Leksell coordinate frame G was fixed to prevent the anterior screw implantation within the temporalis muscle, to avoid interference with the magnetic resonance (MR)-adapter, and taking into account the magnetic field of MR in close proximity to the tentorium. After mounting of indicator box, the MR imaging evaluation should cover both the indicator box and the infratentorial region that deviated from it. The coordinates [X, Y, Za, Arc⁰, Ringa⁰] obtained from Leksell SurgiPlan^® software (Elekta, Stockholm, Sweden) with arc 0⁰ located on the patient's right side were converted to [X, Y, Zb=360-Za, Arc⁰, Ringb⁰=Ringa⁰-180⁰]. The operation was performed in the prone position under general anesthesia in four patients with deep cerebellar (n=3) and brainstem (n=1) tumors. The biopsy results showed two cases of diffuse large B-cell lymphoma, one metastatic braintumor and one glioblastoma. One patient required frame repositioning as a complication. Drawing upon the methodology outlined in existing literature, we anticipate that imparting supplementary expertise could render the stereotactic biopsy of infratentorial tumors more consistent and manageable for the practitioner, thereby facilitating adequate tissue samples and minimizing patient complications.

• Archives of Plastic Surgery
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• v.41 no.6
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• pp.728-733
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• 2014

Background Periareolar Augmentation Mastopexy is one of the most challenging operations in plastic surgery. Problems with scar quality, areolar widening, and distortion are frequent problems that interfere with a predictable result. Methods A retrospective review was performed on fifty consecutive patients who underwent a periareolar augmentation mastopexy with the interlocking approach. Of the 50 patients, 30 had both preoperative and postoperative photographs and were the basis of the study. Results The age of the patients ranged from 19 to 56 years with the average age being 39 years. The postoperative follow-up averaged 9.5 months and the implants averaged 316 mL. There were no deaths, pulmonary embolism, deep vein thrombosis, or infected implants. Four patients had complications following surgery for an overall complication rate of 13%. Two patients developed an infected Gore-Tex suture. Two of these complications were treated with revision surgery. Five patients required reoperation for an overall reoperative rate of 16% (one patient was converted to a full mastopexy). Conclusions As a result of this retrospective study, we have found the interlocking approach to periareolar augmentation/mastopexy to be a safe and reliable operation.

• Journal of Korean Foot and Ankle Society
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• v.24 no.2
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• pp.69-74
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• 2020

Osteochondral lesions of the talus (OLT) can heal and remain asymptomatic, or they can progress to deep ankle pain on weight bearing and the formation of subchondral cysts. Treatment varies from nonoperative treatment to open and arthroscopic procedures. Operative procedures include marrow stimulation techniques (abrasion chondroplasty, multiple drilling, microfracture), osteochondral autografts or allografts, and autologous chondrocyte implantation. Among these treatments, arthroscopic marrow stimulation techniques have been the preferred initial surgical treatment for most OLT. Despite these treatments, many patients complain of persistent pain even after surgery, and many surgeons face the challenge of determining a second line of treatments. This requires a thorough re-evaluation of the patient's symptoms as well as radiological measures. If the primary surgical treatment has failed, multiple operative treatments are available, and relatively more invasive methods can be administered. On the other hand, it is inappropriate to draw a firm conclusion in which methods are superior.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.25 no.1
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• pp.6-14
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• 2012

For integrated complementary metal oxide semiconductor (CMOS) circuits, the lateral spread for two-dimensional (2-D) impurity distributions are very important for the analyzing the devices. The measured two-dimensional SEM data obtained using the chemical etching-method matched very well with the results of the Gauss model for boron implanted samples. But the profiles in boron implanted silicon were deviated from the Gauss model. The profiles in boron implanted silicon were shown a little bit steep profile in the deep region due to backscattering effect on the near surface from the bombardments of light boron ions. From the simulated 3-D data obtained using an analytical model, the 1-D and 2-D data were compared with the experimental data and could be verified the justification from the experimental data. The data of 3-D model were also shown good agreements with the experimental and the simulated data. It can be used in the 3-D chip design and the analysis of microelectro-mecanical system (MEMS) and special devices.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2001.05a
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• pp.349-352
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• 2001

In this paper, novel device structure in order to realize ultra fast and ultra small silicon devices are investigated using ultra-high vacuum chemical vapor deposition(UHVCVD) and Excimer Laser Annealing (ELA) for ultra pn junction formation. Based on these fundamental technologies for the deep sub-micron device, high speed and low power devices can be fabricated. These junction formation technologies based on damage-free process for replacing of low energy ion implantation involve solid phase diffusion and vapor phase diffusion. As a result, ultra shallow junction depths by ELA are analyzed to 10~20 nm for arsenic dosage (2$\times$10$^{14}$ $\textrm{cm}^2$), excimer laser source(λ=248nm) is KrF, and sheet resistances are measured to 1k$\Omega$/$\square$ at junction depth of 15nm.